A CASING, BATTERY, A METHOD OF MANUFACTURING A BATTERY AND METHODS OF OPERATING THE BATTERY

Abstract

A battery with a laminate in which only the anode is exposed at least at one end or side. The laminate may be folded with the anode as the outermost layer. The battery may have a casing with a shoulder portion and an opposite opening for introduction of the laminate. The battery may have a pressure relieve channel extending in a plane of the wall portion. The battery may have a current interruption device positioned at least partly within a concave end cap for saving space.

Claims

1.-13. (canceled)

14. A battery comprising a casing and a charge holding laminate, wherein: the casing has a first and a second electrical terminal and the laminate provided in the casing, the laminate comprises at least three layers: a cathode layer, an anode layer and a separator provided between the cathode layer and the anode layer, wherein, in a cross section of the laminate: the separator forms a U- or V-shaped structure inside which the cathode layer is provided and the anode layer is provided on both sides of the separator and extend farther in the direction of the bottom of the U- or V-shaped structure than the separator and wherein the cathode layer is connected to the first electrical terminal of the casing and the anode layer is connected to the second electrical terminal of the casing.

15. The battery according to claim 14, wherein at least the separator is folded or bent along a first axis and wherein the laminate is folded or bent along or around a second axis which is non-parallel to the first axis.

16. The battery according to claim 14, wherein the laminate is formed as a coil of a folded laminate.

17. The battery according to claim 15, wherein the anode layer is outside of the separator and the cathode layer.

18. The battery according to claim 15, wherein the laminate is folded by folding the separator and anode layers around the cathode layer.

19. The battery according to claim 14, wherein the casing has a central portion having a cavity or channel with a longitudinal axis and a predetermined cross-sectional area in a plane perpendicular to the axis and further comprises: an opening at one end thereof and a cap portion blocking the opening and forming the first or the second electrical terminal.

20. The battery according to claim 19, wherein an opposite end portion of the casing forms the other of the first and the second terminal.

21. The battery according to claim 20, wherein an electrically conducting, resilient material is provided between the other of the cathode layer and the anode layer and the opposite end portion of the casing.

22. The battery according to claim 14, further comprising one or more tab portions extending from at least one of the cathode layer and the anode layer.

23. The battery according to claim 14, further comprising a wall part and a vent element formed in the wall part, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

24. The battery according to claim 14, further comprising: a concave end cap, the casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing, and a thermal switch comprising: a connection portion electrically connected to one of the anode layer and the cathode layer and being configured to move between a first position and a second position, where, in the first position, the connection portion is electrically connected to the end cap within the cavity, and in the second position, the connection portion is at a at least a predetermined distance from the end cap so as to not be electrically connected to the end cap, and a thermally reactive element configured to position the end connection portion in the first position when the temperature is below a threshold temperature and in the second position when the temperature is above the threshold temperature.

25. The battery according to claim 14, wherein the casing has: a central portion having a cavity or channel with a longitudinal axis and a predetermined cross-sectional area in a plane perpendicular to the axis, a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel, and an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion.

26. A method of manufacturing a battery, the method comprising: (1) providing a charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, wherein, in a cross section of the laminate: the separator forms a U- or V-shaped structure inside which the cathode layer is provided and the anode layer is provided on both sides of the separator and extend farther in the direction of the bottom of the U- or V-shaped structure than the separator and; (2) folding or bending the laminate; (3) providing the folded/bent laminate in a casing having a first and a second electrical terminal; (4) connecting the cathode layer to the first electrical terminal of the casing and the anode layer to the second electrical terminal of the casing.

27. The method according to claim 26, wherein the first and/or folding provides the anode layer outside of the separator and the cathode layer.

28. The method according to claim 26, wherein step 3 comprises: providing the folded/bent laminate in a casing having a central portion having a cavity or channel with a longitudinal axis and a predetermined cross-sectional area in a plane perpendicular to the axis and providing the folded/bent laminate into the cavity/channel through an opening at one end thereof and the method further comprising the step of blocking the opening with a cap portion forming the first electrical terminal.

29. The method according to claim 28, wherein the cap portion forms one of the first and second terminal.

30. The method according to claim 29, wherein an opposite end portion of the casing forms the other of the first and second terminal.

31. The method according to claim 30, further comprising providing an electrically, resilient material between the other of the cathode layer and the anode layer and the opposite end portion of the casing.

32. The method according to claim 26, further comprising the step of providing one or more tab portions extending from at least one of the cathode layer and the anode layer.

31. The method according to claim 26, wherein step 4 comprises providing a casing comprising an inner channel or cavity closed at one end by an electrically conducting cap portion electrically connected to a layer of the laminate and a casing portion, wherein the step of providing the casing portion comprises: providing a first portion part with a first opening, the first opening opening into the cavity, providing a first material on the first portion part, the first material extending from the first opening, providing a second material on the first portion part and the first material and with a second opening at the first material, the second opening opening toward the surroundings of the battery.

Description

[0209] In the following, preferred embodiments of the invention will be described with reference to the drawings, wherein:

[0210] FIG. 1 illustrates the layers of a charge holding laminate,

[0211] FIG. 2 illustrates additional layers of the laminate,

[0212] FIG. 3 illustrates how to stack/roll the laminate for a battery,

[0213] FIG. 4 illustrates a preferred casing type,

[0214] FIG. 5 illustrates a rolled laminate with end caps,

[0215] FIG. 6 illustrates a Current Interruption Device,

[0216] FIG. 7 illustrates a vent in an end cap,

[0217] FIG. 8 illustrates a cross section of a vent,

[0218] FIG. 9 illustrates a reservoir for use in a vent,

[0219] FIG. 10 illustrates an embodiment of a folded laminate, and

[0220] FIG. 11 illustrates an embodiment with combined separator layers.

[0221] In FIG. 1, a charge holding sheet or jelly roll sheet 10 is illustrated having, as is usual, an anode layer 12, a separator layer 14 and a cathode layer 16. A conductive tab 18 is connected to the cathode layer.

[0222] In FIG. 2, a typical build-up of the layers is seen, where the anode 12 comprises a current collector material 121, such as aluminium an anode material 123, and where the cathode 16 comprises a current collector material 161, such as cupper and a cathode material 163.

[0223] A very large number of anode and cathode materials exist. The present invention is not limited to a particular battery chemistry.

[0224] Usual anode materials may be: [0225] Lithium titanium oxide (Li.sub.4Ti.sub.5Oi.sub.2; LTO) [0226] Carbon-coated lithium titanium oxide (C-LTO) [0227] Silicon-graphite (Si—C) composites with different mass ratios [0228] Silicon monoxide nanowire (SiO.sub.x—NW) [0229] Silicon monoxide nanowire-graphite (SiO.sub.x—C) composite [0230] Tin oxide (SnO.sub.2)/doped tin oxide [0231] Graphite [0232] Cu.sub.2Sb [0233] NiSb [0234] ZnSb [0235] MoSb [0236] MnSb [0237] InSb [0238] AgSb [0239] MgSb [0240] Ti Sb [0241] VSb [0242] CrSb

[0243] Typical cathode materials are: [0244] Lithium cobalt oxide (LiCoO.sub.2; LCO) [0245] Lithium nickel cobalt oxide (LiNi.sub.0.8Co.sub.0.15Al0.0.sub.5O.sub.2; NCA) [0246] Lithium manganese oxide (LiMn.sub.2O.sub.4; LMO) [0247] Lithium (excess) manganese oxide (Li.sub.2MnO.sub.3) [0248] Doped lithium manganese oxide (LiMn.sub.2−xM.sub.xO.sub.4) [0249] Lithium manganese nickel oxide (LiMn.sub.1.5Ni.sub.0.5O.sub.4; LMNO) [0250] Lithium manganese nickel cobalt oxide composite (Li.sub.1+xMn.sub.xNi.sub.yCo.sub.zO.sub.2) [0251] Iron Phosphate (FePO.sub.4; FP) [0252] Aluminum phosphate (AlPO.sub.4) [0253] Lithium cobalt phosphate (LiCoPO.sub.4) [0254] Lithium iron phosphate (LiFePO.sub.4; LFP) [0255] Doped lithium cobalt phosphate (LiCo.sub.1−xMxPO.sub.4; M: Mn, Fe, Co, V, Gd, Mg) [0256] Ti-doped lithium manganese nickel oxide (LiMn.sub.1−xTi.sub.xNi.sub.5O.sub.4; LTMNO) [0257] Iron disulfide (FeS.sub.2) [0258] Titanium disulfide (TiS.sub.2) [0259] Sodium manganese oxide (Na.sub.0.44MnO.sub.2; Na.sub.2Mn.sub.5O.sub.10) [0260] Sodium manganese nickel oxide (NaMn.sub.2−xNi.sub.xO.sub.4) [0261] Doped sodium manganese nickel oxide (NaNi.sub.0.33Fe.sub.xMn.sub.0.333Mg.sub.ySn.sub.zO.sub.2) [0262] Sodium cobalt oxide (Na.sub.xCoO.sub.2) [0263] Sodium iron manganese oxide (Na.sub.x[Fe.sub.0.5Mn.sub.0.5]O.sub.2) [0264] Sodium lithium nickel manganese oxide (Na.sub.0.85Li.sub.0.17Ni.sub.0.21Mn.sub.0.64O.sub.2) [0265] Sodium iron phosphate (NaFePO.sub.4—Olivine) [0266] Sodium cobalt mixed phosphates (Na.sub.4Co.sub.3(PO.sub.4).sub.2P.sub.2O.sub.7) [0267] Sodium cobalt manganese nickel mixed phosphates (Na.sub.4Co.sub.2.4Mn.sub.0.3Ni.sub.0.3(PO.sub.4).sub.2P.sub.2O.sub.7) [0268] Sodium iron mixed phosphates (Na.sub.4Fe.sub.3(PO.sub.4).sub.2P.sub.2O.sub.7) [0269] Sodium iron sulfate (NaFe(SO.sub.4).sub.2; Eldfellite mineral)

[0270] The separator 14 preferably is porous so that ions may travel between the anode and cathode sheets. Often, the separator is usually saturated with a separator liquid for the ions to travel in. Solid electrolytes are also known.

[0271] An additional separator layer may be provided on top of the cathode material in order to prevent direct contact between the cathode material and another layer of this material or the anode material.

[0272] In FIG. 3, different manners of building a battery are illustrated. To the left, a flat structure is seen where the separator is shaped into a Z-shape (serpentine) with layers of anode and cathode alternately positioned on the separator layer, so that between an anode layer and a cathode layer, a layer of the separator is seen. The final shape is illustrated to the lower left.

[0273] At the centre of FIG. 3, a similar structure is achieved by not providing the separator on a roll but also as sheets.

[0274] To the right, lamination of sheets of the battery are seen as well as two manners of rolling the laminate. To the lower left of this embodiment, a standard cylindrical roll is seen. To the right, a so-called prismatic roll is seen which is rolled, such as over a linear or flat bobbin or element, with a more oblong or oval structure or shape.

[0275] Reverting to FIG. 1, a folding line A is illustrated. In preferred embodiments of the invention, the laminate is folded along an axis, such as A, before rolling. In this manner, the outer layer of the roll is of the anode material also at one end thereof. Clearly, the laminate may be folded multiple times, such as along multiple axes parallel to A.

[0276] The rolling then preferably is along a direction parallel to A—around an axis perpendicular to A.

[0277] In addition, it is seen in FIGS. 1 and 2 that the cathode material, in the view of FIG. 1, lays completely within the separator material and the anode material and that the separator lies within the anode material on 3 sides and extends further out opposite to the bending. Thus, when rolled, and even when not folded, the anode material will also be covering the separator and the cathode at one end. Actually, the end of the roll may be deformed (compressed) at one end such as when contacting an end portion of the battery casing without risking contact between the anode material and the cathode material. Then, contact to an end portion (see further below) may simply be obtained by simple biasing of the end of the roll toward that end portion.

[0278] In FIG. 10, the result of a bent laminate where the cathode 16 has been folded to obtain twice the thickness and where the separator is folded to generate a U-shaped lower portion. The anode 12 is also folded to become U-shaped at the bottom 141.

[0279] In FIG. 11, an alternative method is seen where the cathode layer is a single layer, the separator has been provided as two layers which are connected to form a V-shaped portion 142 and where the anode 12 is provided as two individual layers.

[0280] Common to these embodiments, which may also be mixed, is that the separator prevents any electrical contact between the anode and cathode at this lower end portion of the laminate. Thus, a number of manners of contacting the anode layer at this position lend themselves—such as by simply forcing the end of the laminate into an electrically conducting, resilient material also in contact with a terminal of the battery.

[0281] A serpentine folding would have the same functionality. This type of folding is interesting in relation to pouch batteries.

[0282] In this situation, when rolling the folded laminate, the anode layer will contact itself in the roll. The same may be the situation for the cathode layer in the folded laminate. This may be taken into account when deciding on the dimensions of the laminate.

[0283] The cathode layer may be made to have a smaller area, such as only the upper half in FIG. 2. Then, the folding is a folding of the separator and anode layer around the axis A and thus around the unfolded cathode layer.

[0284] Also, when the laminate has been folded as described, one end portion of the roll will also expose only the anode material. In that manner, casing of the laminate roll is extremely simple, in that all of the end portion and the outer portion along the casing sides will be anode material. Then, it may not even be necessary to provide an electrical insulation between the jelly roll and the battery casing and the anode end cap.

[0285] Actually, also the sides of the roll expose only the laminate, so this side of the laminate may be connected to the sides of the casing in the same manner if desired.

[0286] The cathode is accessible, such as via the tab 18, at the opposite end of the roll. Naturally, a tab may be provided as illustrated at 18′ which would extend out of the roll at the circumference thereof.

[0287] Multiple tabs may be provided for higher current transport capabilities and better thermal balance.

[0288] The tabs 18 may be made of any material, such as pyrolytic graphite sheets which have good mechanical properties in addition to very high electrical and thermal conductivity and a good resistance to corrosion. Such tabs may be gold plated to prevent corrosion thereof. Clearly, an insulation layer, such as a sol-gel, may be provided closer to the cathode material in order to prevent electrical contact to the anode layer.

[0289] FIG. 4 illustrates a preferred battery casing 20 type having a central volume 201 for receiving at least a portion of the rolled laminate as well as a shoulder portion 203 having an opening 205 for gaining electrical access to the laminate from outside of the casing. In an alternative embodiment, the shoulder portion 203 could be replaced by a complete closing of the casing, such as if the casing is connected to the anode of the laminate.

[0290] At the opposite end of the battery casing 20, an opening 207 is provided through which the rolled laminate may be introduced into the volume 201.

[0291] In FIG. 5, a battery assembly 30 is illustrated having the actual laminate roll 301, from which a number of tabs 18 extend which are connected to a cathode end portion 310. As the environment in a battery is rather corrosive, it may be preferred to provide a corrosion resistive coating, such as gold, on both the end portion 310 and the tabs 18. The tabs may be made of carbon fullerenes such as PGS which also has the advantage of providing and retaining a good resilience to maintain a good physical contact between the tab and the end cap.

[0292] The opposite (upper) end portion of the laminate preferably exposes only the anode layer, so that this portion may be simply biased toward an anode end portion 305. Optionally, a resilient, electrically conducting material, such as a gel, may be provided between the end portion 305 and the end of the roll 301. As will be described below, the end portion 305 is optional.

[0293] The tabs 18 may merely be biased toward the end portion 310, such as if made flexible and elastically deformable. Alternatively, the tabs may be welded, soldered or glued to the end portion 310.

[0294] The assembly 30 may be fully or partly assembled before introduction into the casing 20. Otherwise, the end portion 310 may simply be provided in the volume 201, where after the roll 301 may be provided therein and the end portion 305 provided before the casing is closed. Alternatively, the battery assembly of FIG. 5 may be rotated 180 degrees so that the “anode end” is introduced into the casing 20 first. Then, the upper closing (see below) may comprise an opening for access to the end portion 310 connected to the cathode layer.

[0295] The shoulder portion 203 prevents portion 310 from exiting the volume 201. The end portion 310 may seal toward the shoulder portion or other portions of the casing to provide an air tight seal.

[0296] Naturally, electrical insulation may be provided between the casing material and the end portion 310 which is connected to the cathode material.

[0297] The end portion 310 is exposed via the opening 205, so that electrical connection from the outside is possible.

[0298] The upper end, in the drawing, of the battery casing may be closed in a number of manners. The casing may be longer than the length of the end portion 310 and the roll 301, so that an upper portion of the casing may be deformed inwardly to close the volume or, if the end portion 305 is provided, seal toward the end portion 305. If the end portion 305 is not provided, the casing material may be deformed to completely seal the volume 21 at that end. The above contacting to the upper end of the roll 301 may be performed equally well to inwardly directing portions of the casing material.

[0299] In FIG. 4, inwardly bent portions are illustrated with hatched lines at two different positions.

[0300] In FIG. 4, the upper portions of the casing 20 are illustrated as flaring outwardly. This has the advantage that the assembly 30 may more easily be introduced into the volume 201. In addition to this, the inner surface of the casing may be coated with a material giving a smooth surface to further assist in the introduction of the assembly 30 into the volume 201.

[0301] A tight fit is desired, so that the roll preferably has an outer shape, such as a cross sectional shape in a direction perpendicular to the axis around which the roll was rolled, conforming to an inner shape of the casing 20.

[0302] A number of advantages may be made in relation to battery casings, such as that of FIG. 4. Firstly, many battery casings are made of deep drawn steel. Deep drawing, however, results in stress fractures which provide very rugged inner surfaces which require the addition of a protective layer to prevent damaging of the laminate roll during insertion. This layer takes up valuable space.

[0303] The battery casing 20 may instead be manufactured from a rod shaped material which may be deformed or worked to provide the shoulder portion 203 and, if desired, the flaring portion 207. Rod shaped materials may have a smoother inner surface, as they may have stress fractures only at the shoulder portions and the flaring portion (if provided) so that no or only a thin layer of a protective material needs be provided in the volume 201.

[0304] A weight saving may be obtained if, instead of steel, a lighter material is used, such as magnesium, beryllium, titanium, aluminium, or alloys comprising such materials, such as AZ31, lithium, silicon or the like. The material may be enforced such as by fibres or microspheres. Desired properties are compressive strength, tensile strength, heat conduction and resistance to corrosion.

[0305] Clearly, if the casing is made of a material which would react with a material of the laminate, such as the anode material, due to ion transport between these, a coating may be provided in the casing to prevent this. This coating may be electrically insulating but need not be thick.

[0306] A suitable coating type is a sol-gel which may be both electrically insulating may provide a smooth surface and be very thin. Sol-gels may be applied by spraying, coating, spin coating, dip coating or the like.

[0307] A large number of cheap and useful sol-gels are available. Interesting properties are a high dielectric constant, low weight, effective even as a thin layer, impermeable to electrolyte and ions, resistant to battery chemistry, high heat conductance etc.

[0308] Other coating types may be coatings with metals, such as nickel or gold, or polymers of any type. The coating may have multiple layers. For example, it may be desired to provide an initial gold plating in order for a later coating, such as a sol-gel, to be sufficiently attached. Internal metal plating has the advantage that electrical connection between the anode layer and the casing is automatic.

[0309] A coating may be provided on both the inner and outer side of the casing material. An outer coating may be desirable e.g. in situations where the casing material is of a corrosion/oxidation prone material, such as magnesium or aluminium.

[0310] Clearly, even though the above embodiments have been described with the anode material being the largest and the outer-most material. The laminate may be inverted so that the cathode layer is the outermost layer if desired.

[0311] Batteries typically comprise a safety switching mechanism, often called a Current Interruption Device (CID), which is intended to prevent further current delivery, when the laminate overheats and/or if a pressure therein becomes excessive.

[0312] A new CID is illustrated in FIG. 6 in which it is provided in the end portion 310. The end portion 310 has, seen from the outside, a convex shape with an element for positioning in the opening 205. This element forms a convex conductor for engagement from the outside of the battery. The inner concavity is utilized to provide a shallower CID.

[0313] The CID has, in the direction of the drawing, an upper contact element 311 for contacting the outer, convex conductor 312 of the end portion 310. The contact element 311 is connected to an inner conducting element 313 which, at its lower surface, is connected to the laminate roll. In the inner conducting element 313, a cavity 314 exists into which the contact element 311 may move, if temperature sensitive controlling elements 315 experience a sufficiently high temperature.

[0314] Electrical connection may be provided from the inner conducting element 313 to the conducting element 311 via the temperature sensitive controlling elements 315. Alternatively, another element may be provided for ensuring this contact.

[0315] The temperature sensitive controlling element ensures contact between the contact element and the convex conductor during normal operation but is/are configured to move, such as translate and/or rotate, the upper element 311 into the cavity 314, when the temperature exceeds a threshold temperature. Then, the contact between the contact element and the convex conductor is broken and current delivery from the laminate prevented.

[0316] The temperature sensitive controlling element may be any type of material configured to change shape with temperature, such as memory materials or bimetallic actuators.

[0317] Preferably, the threshold temperature is higher than 50 degrees Celsius, such as higher than 60, 70, 80, 90 or 100 degrees or even higher than 110, 120, 130 or 140 degrees. On the other hand, the threshold temperature preferably is below 180 degrees, such as below 160, 150 or 140 degrees, such as below 130 degrees Celsius, such as below 120 degrees, 110 degrees or 100 degrees.

[0318] Naturally, CIDs of this type may be implemented anywhere in a battery, but the present embodiment is preferred at the positive terminal of circular batteries, as they usually have a convex portion, as a part of the cathode terminal, inside which the CID may be positioned so as to take up as little space as possible within the main volume of the battery casing.

[0319] Batteries also usually comprise an over pressure valve allowing gasses to escape the casing interior. Often such valves are irreversible in the sense that they are formed as weak gaskets which break along which a controlled breaking and thus venting takes place, if the internal pressure in the battery exceeds a pressure threshold.

[0320] A new type of vent is seen in FIG. 7, where a vent 400 is formed over a portion of the battery casing. In the present example, a vent 400 is formed in the end cap 310, but may in principle be positioned anywhere in a battery casing.

[0321] The vent 400 comprises a vent channel 410 with one opening 412 to the surroundings of the battery and an opening 414 toward the inner volume 201 of the battery casing.

[0322] The vent channel may have any desired length and width and extends in a plane inside the portion, here the end cap, of the casing. When the channel 410 extends along a plane of the casing portion, it may be much longer than a width or thickness of the casing material. In this context, the plane may be straight or bent. The channel may be selected to be serpentine or very meandering in order to define the gas flow therein. When the end cap is a plane element, the plane in which vent channel extends, may be plane. If, on the other hand, the vent 400 is provided in a curved portion of a battery, such as on a side of a cylinder shaped casing, the vent channel may extend inside the wall and along the curvature of the wall portion. A straight vent may be obtained if extending along a longitudinal direction of the cylinder.

[0323] Even when the vent channel 410 is open, gas transport over it may be prevented or at least sufficiently low, if the channel is sufficiently long, sufficiently narrow and/or sufficiently meandering. The channel need not have the same width along its length, so also narrowed portions will act to prevent gas transfer. This is at least the situation when the pressure difference over the channel is sufficiently low. At higher pressure differences, the channel should allow a predetermined gas flow to allow the pressure difference to reduce or at least not grow.

[0324] Another manner of preventing gas flow at low pressure differences is to provide a material 416 in the channel. A sufficiently high pressure difference may force the material 416 out of the channel 410 to allow gas transport.

[0325] One manner of providing a channel with a material therein may, c.f. FIG. 8, be obtained by providing the casing portion, such as the end cap, as a multiple of layers. Then, a lower layer with the opening 414 may be formed on which the material 416 is positioned. After that, a top layer may be provided and the opening 412 therein. The material 416 then may form the channel as it prevents the material of the top layer from occupying the space reserved by the material.

[0326] The material may be a polymer, a wax or the like.

[0327] Naturally, the material may be removed by a sufficiently high pressure difference, but the material preferably is softened, such as melted or evaporated, at a predetermined elevated temperature, such as a temperature above 130, 140 or 120 degrees Celcius, such as above 80 degrees. An increased temperature results in an increased pressure and thus requires the opening of the channel.

[0328] Subsequently, the channel may remain open, which may not be preferred.

[0329] A solution may be seen in FIG. 9, where a reservoir 420 is connected to the channel 410. Then, when an overpressure forces the material 416 also into the reservoir 420, where the material may remain until the pressure in the channel 410 drops, where after the material may again travel into the channel 410 to again prevent gas transport through the channel 410. Not all of the material may travel into the reservoir, but enough to re-close the channel 410 would suffice. Clearly, the amount of material and the size and position of the reservoir may be adapted so that the channel may be re-closed a single time or multiple times.

[0330] When forced into the reservoir, an overpressure will be created therein which will act to force the material out of the reservoir, when the pressure in the channel drops.

[0331] The material, as mentioned above, may be softened due to a temperature increase. In that manner, when the pressure difference decreases and the temperature drops, the material forced back onto the channel may liquefy/solidify and thereby effectively seal the channel again.

[0332] The size of the reservoir may be adapted to the amount of material in the channel or at least to an amount required to re-close the channel. Additional material initially in the channel may be expelled from the channel due to the pressure increase and gas flow.

[0333] The reservoir may be positioned closer to the opening 414 toward the interior of the casing, as the remainder of the channel (the portion of the channel between the opening to the reservoir and the opening 412) may act to provide a counter pressure keeping the absolute pressure in the reservoir rather high. Then, when the pressure drop decreases, the material will be re-introduced into the channel with this counter pressure assisting in maintaining the material in the channel instead of expelling the material from the channel. Also, when a length of the channel exists between the opening toward the reservoir and the opening 412, the material forced out of the reservoir will be able to settle in the channel instead of being forced out of the opening 412.

[0334] Clearly, multiple reservoirs may be provided if desired.

[0335] The reservoir may initially be empty (except for a gas) in order for it to be able to receive the material. The pressure in the reservoir will increase, whereby the material will compress the gas to occupy a part of the reservoir. When the temperature and the pressure in the channel decreases, the compressed gas in the reservoir will force the material back into the channel.

[0336] Alternatively, the reservoir may be pre-filled with material.

[0337] In the above embodiments, a number of technologies are presented which may be combined into a single battery with much higher energy density and better performance than other, known batteries.

[0338] However, the technologies may also be used individually. For example, a folded and rolled laminate may be used in already known battery casings, as may the CID and the vent channel.

[0339] The above battery casing may be used for standard laminate rolls and standard end portions if desired.

[0340] Also, the CID and vent channel may be employed in other types of batteries, such as pouch batteries which may also or alternatively receive a folded, rolled laminate with prismatic shape.

EMBODIMENTS

[0341] 1. A battery comprising a casing and a charge holding laminate, wherein:

the casing has a first and a second electrical terminal and
the laminate provided in the casing, the laminate comprises at least three layers:
a cathode layer
an anode layer and
a separator provided between the cathode layer and the anode layer,
wherein, in a cross section of the laminate:
the separator forms a U- or V-shaped structure inside which the cathode layer is provided and
the anode layer is provided on both sides of the separator and extend farther in the direction of the bottom of the U- or V-shaped structure than the separator and
wherein the cathode layer is connected to the first electrical terminal of the casing and the anode layer is connected to the second electrical terminal of the casing.

[0342] 2A. A battery according to embodiment 1, wherein at least the separator is folded or bent along a first axis and wherein the laminate is folded or bent along or around a second axis which is non-parallel to the first axis.

[0343] 2. A battery according to embodiment 1 or 2A, wherein the laminate is formed as a coil of a folded laminate.

[0344] 3. A battery according to embodiment 2A or 2, wherein the anode layer is outside of the separator and the cathode layer.

[0345] 4. A battery according to embodiment 2A, 2 or 3, wherein the laminate is folded by folding the separator and anode layers around the cathode layer.

[0346] 5. A battery according to any of the preceding embodiments, wherein the casing has a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis and further comprises:

an opening at one end thereof and
a cap portion blocking the opening and forming the first or the second electrical terminal.

[0347] 6. A battery according to embodiment 5, wherein an opposite end portion of the casing forms the other of the first and the second terminal.

[0348] 7. A battery according to embodiment 6, wherein an electrically conducting, resilient material is provided between the other of the cathode layer and the anode layer and the opposite end portion of the casing.

[0349] 8. A battery according to any of the preceding embodiments, further comprising one or more tab portions extending from at least one of the cathode layer and the anode layer.

[0350] 9. A battery according to any of the preceding embodiments, further comprising a wall part and a vent element formed in the wall part, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

[0351] 10. A battery according to any of the preceding embodiments, further comprising:

a concave end cap, the casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing, and
a thermal switch comprising: [0352] a connection portion electrically connected to one of the anode layer and the cathode layer and being configured to move between a first position and a second position, where, in the first position, the connection portion is electrically connected to the end cap within the cavity, and in the second position, the connection portion is at a at least a predetermined distance from the end cap so as to not be electrically connected to the end cap, and [0353] a thermally reactive element configured to position the end connection portion in the first position when the temperature is below a threshold temperature and in the second position when the temperature is above the threshold temperature.

[0354] 11. A battery according to any of the preceding embodiments, wherein the casing has:

a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis,
a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder,
a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel, and
an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion.

[0355] 12. A method of manufacturing a battery, the method comprising: [0356] 1. providing a charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, wherein, in a cross section of the laminate: [0357] the separator forms a U- or V-shaped structure inside which the cathode layer is provided and [0358] the anode layer is provided on both sides of the separator and extend farther in the direction of the bottom of the U- or V-shaped structure than the separator and [0359] 2. folding or bending the, [0360] 3. providing the folded/bent laminate in a casing having a first and a second electrical terminal, [0361] 4. connecting the cathode layer to the first electrical terminal of the casing and the anode layer to the second electrical terminal of the casing.

[0362] 14. A method according to embodiment 13, wherein the first and/or folding provides the anode layer outside of the separator and the cathode layer.

[0363] 15. A method according to any of embodiments 12-14, wherein step 3 comprises: [0364] providing the folded/bent laminate in a casing having a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis and [0365] providing the folded/bent laminate into the cavity/channel through an opening at one end thereof and
the method further comprising the step of blocking the opening with a cap portion forming the first electrical terminal.

[0366] 16. A method according to embodiment 15, wherein the cap portion forms one of the first and second terminal.

[0367] 17. A method according to embodiment 16, wherein an opposite end portion of the casing forms the other of the first and second terminal.

[0368] 18. A method according to embodiment 17, further comprising providing an electrically, resilient material between the other of the cathode layer and the anode layer and the opposite end portion of the casing.

[0369] 19. A method according to any of embodiments 12-18, further comprising the step of providing one or more tab portions extending from at least one of the cathode layer and the anode layer.

[0370] 20. A method according to any of embodiments 12-19, wherein step 4 comprises providing a casing comprising an inner channel or cavity closed at one end by an electrically conducting cap portion electrically connected to a layer of the laminate and a casing portion,

wherein the step of providing the casing portion comprises: [0371] providing a first portion part with a first opening, the first opening opening into the cavity, [0372] providing a first material on the first portion part, the first material extending from the first opening, [0373] providing a second material on the first portion part and the first material and with a second opening at the first material, the second opening opening toward the surroundings of the battery.

[0374] 21. A method according to any of embodiments 12-20, further comprising the step of venting gas from an inner cavity of a battery, the method comprising venting the gas to surroundings of the battery via a vent element formed in a wall part of the battery, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward the surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

[0375] 22. A method of switching of a battery according to any of embodiments 1-11 when overheating, the method comprising:

providing the battery with: [0376] a concave end cap, [0377] a casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing, and [0378] a thermal switch comprising a connection portion, in electrical contact with one of the anode layer and the cathode layer, and a thermally reactive element configured to move the connection portion,
the method comprising: [0379] when the temperature is below a threshold temperature, the thermally reactive element positions the connection portion in a first position in electrical contact with the end cap in the cavity thereof and [0380] when the temperature is above the threshold temperature, the thermally reactive element positions the connection portion in a second position in which it has at least a predetermined minimum distance to the end cap so as to not be electrically connected to the end cap,

[0381] 23. A method according to any of embodiments 12-23, the method comprising:

providing the casing having: [0382] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0383] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0384] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel,
positioning an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion,
providing the charge holding laminate in the cavity/channel,
electrically connecting one of the anode layer and the cathode layer of the laminate to the cap portion,
closing the second end portion of the casing and electrically connecting the other of the anode layer and the cathode layer to an electrical terminal of the casing.

[0385] 24. A method of assembling a battery comprising a charge holding laminate and a casing, the method comprising:

providing the casing having: [0386] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0387] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0388] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel,
positioning an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion,
providing a charge holding laminate in the cavity/channel, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer,
electrically connecting one of the anode layer and the cathode layer of the laminate to the cap portion,
closing the second end portion of the casing and electrically connecting the other of the anode layer and the cathode layer to an electrical terminal of the casing.

[0389] 25. A method according to embodiment 24, wherein the closing step comprises deforming the second end portion.

[0390] 26. A method according to embodiment 24 or 25, wherein the step of providing the casing comprises providing a casing having a funnel-shaped second portion.

[0391] 27. A method according to any of embodiments 24-26, wherein the step of providing the casing comprises providing a casing of magnesium, beryllium, titanium, aluminium, or alloys comprising such materials, such as AZ31, or lithium, silicon or the like and covering an inner surface thereof with a sol-gel.

[0392] 28. A method according to embodiment 27, wherein the step of providing the casing further comprises providing the casing with an outer, oxidation preventing layer.

[0393] 28A. A method according to any of embodiments 24-28, where the method of providing the casing comprises cutting a tube-shaped element into a plurality of casing preforms and subsequently machining each casing preform to form casings therefrom.

[0394] 29. A method according to any of embodiments 24-28 and 28A, wherein the step of providing the charge-holding laminate comprises proving a charge holding laminate having one or more tab portions extending from at least one of the anode layer and the cathode layer, and wherein the step of electrically connecting the one layer to the cap portion comprises providing electrical contact between one or more of the tabs and the cap portion.

[0395] 30. A method according to any of embodiments 24-29, further comprising the step of electrically connecting the other of the anode layer and the cathode layer to an electrical terminal of the casing.

[0396] 31. A method according to embodiment 30, wherein the electrical terminal of the casing is an end portion of the casing at the second end thereof, and wherein the step of electrically connecting the other of the anode layer and the cathode layer to the electrical terminal comprises providing an electrically conductive and resilient material between the other layer and the end portion.

[0397] 32. A method according to any of embodiments 24-31, wherein the step of providing the charge holding laminate comprises: [0398] 1. providing a charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, [0399] 2. firstly folding or bending the laminate along or around a first axis, and [0400] 3. Subsequently folding or bending the laminate along or around a second axis not parallel to the first axis.

[0401] 33. A method according to any of embodiments 24-32, the wherein the step of providing the casing portion or end cap comprises:

providing a first portion part with a first opening, the first opening opening into the cavity,
providing a first material on the first portion part, the first material extending from the first opening,
providing a second material on the first portion part and the first material and with a second opening at the first material, the second opening opening toward the surroundings of the battery.

[0402] 34. A method of venting gas from an inner cavity of a battery assembled by the method of any of embodiments 24-33, the method comprising venting the gas to surroundings of the battery via a vent element formed in a wall part of the battery, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward the surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

[0403] 35. A method of switching of a battery, assembled by the method of any of embodiments 24-33, when overheating, wherein the end cap is concave, the method comprising: [0404] when the temperature is below a threshold temperature, the thermally reactive element positions the connection portion in a first position in electrical contact with the end cap in the cavity thereof and [0405] when the temperature is above the threshold temperature, the thermally reactive element positions the connection portion in a second position in which it has at least a predetermined minimum distance to the end cap so as to not be electrically connected to the end cap.

[0406] 36. A casing for use in the method of any of embodiments 24-35, the casing having: [0407] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0408] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0409] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel, and [0410] an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion.

[0411] 37. A casing according to embodiment 36, wherein the casing has a funnel-shaped second portion.

[0412] 38. A casing according to any of embodiments 36 and 37, the casing being of magnesium, magnesium, beryllium, titanium, aluminium, or alloys comprising such materials, such as AZ31, or lithium, silicon or the like, the inner surface of of the casing being covered with a sol-gel.

[0413] 39. A casing according to embodiment 38, further comprising an outer, oxidation preventing layer.

[0414] 40. The casing according to any of embodiments 36-38, the casing further comprising a charge holding laminate positioned in the cavity/channel, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, wherein one of the anode layer and the cathode layer of the laminate is electrically connected to the cap portion.

[0415] 41. The casing according to embodiment 40, wherein the charge holding laminate has one or more tab portions extending from at least one of the anode layer and the cathode layer and being in electrical contact with the cap portion.

[0416] 42. A battery comprising the casing according to any of embodiments 36-41, the battery further comprising a charge holding laminate provided in the casing.

[0417] 43. A battery provided by the method according to any of embodiments 24-33, the battery comprising:

a casing having: [0418] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0419] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0420] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel,
an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion, and
a charge holding laminate in the cavity/channel, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer,
where one of the anode layer and the cathode layer of the laminate is electrically connected to the cap portion, and
the second end portion of the casing is closed by a second end cap electrically connected to the other of the anode layer and the cathode layer.

[0421] 44. A battery according to embodiment 42, further comprising an electrically conductive and resilient material electrically connecting the second end cap to the other layer.

[0422] 45. A battery according to any of embodiments 42-44, wherein the casing has a first and a second electrical terminal, the laminate is folded or bent along or around at least two non-parallel axes and is provided in the casing and wherein cathode layer is connected to the first electrical terminal of the casing and the anode layer is connected to the second electrical terminal of the casing.

[0423] 46. A battery according to any of embodiments 42-45, the casing comprising an inner cavity closed at one end by an electrically conducting cap portion electrically connected to a layer of the laminate, the battery further comprising a wall part and a vent element formed in the wall part, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

[0424] 47. A battery according to any of embodiments 42-46, comprising:

a concave end cap,
a casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing, and
a thermal switch comprising: [0425] a connection portion electrically connected to one of the anode layer and the cathode layer and being configured to move between a first position and a second position, where, in the first position, the connection portion is electrically connected to the end cap within the cavity, and in the second position, the connection portion is at a at least a predetermined distance from the end cap so as to not be electrically connected to the end cap, and [0426] a thermally reactive element configured to position the end connection portion in the first position when the temperature is below a threshold temperature and in the second position when the temperature is above the threshold temperature.

[0427] 48. A battery with a casing and a charge holding laminate provided in an inner cavity closed at one end by an electrically conducting cap portion electrically connected to a layer of the laminate,

the battery further comprising a wall part and a vent element formed in the wall part, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

[0428] 49. A battery according to embodiment 48, further comprising a solid, gel or liquid material with a predetermined melting or evaporation temperature in the interval of 85-120° C., the material being positioned in the channel.

[0429] 50. A battery according to embodiment 48 or 49, further comprising one or more reservoirs provided in the wall part, each reservoir having a single opening, each single opening opening into the channel.

[0430] 51. A battery according to any of embodiments 48-50, wherein: [0431] the casing has a first and a second electrical terminal and [0432] the laminate comprises at least three layers: [0433] a cathode layer [0434] an anode layer and [0435] a separator provided between the cathode layer and the anode layer,
wherein the laminate is folded or bent along or around at least two non-parallel axes (first around one axis and then the folded/bent laminated is further folded/bent along another axis) and is provided in the casing and
wherein cathode layer is connected to the first electrical terminal of the casing and the anode layer is connected to the second electrical terminal of the casing.

[0436] 52. A battery according to any of embodiments 48-51, the casing having: [0437] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0438] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0439] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel, and [0440] an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion.

[0441] 53. A battery according to any of embodiments 48-52, the battery comprising:

a concave end cap, the casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing,
a charge holding laminate in the casing, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, and
a thermal switch comprising: [0442] a connection portion electrically connected to one of the anode layer and the cathode layer and being configured to move between a first position and a second position, where, in the first position, the connection portion is electrically connected to the end cap within the cavity, and in the second position, the connection portion is at a at least a predetermined distance from the end cap so as to not be electrically connected to the end cap, and [0443] a thermally reactive element configured to position the end connection portion in the first position when the temperature is below a threshold temperature and in the second position when the temperature is above the threshold temperature.

[0444] 54. A method of producing a battery according to any of embodiments 48-53, the method comprising providing a casing comprising an inner channel or cavity closed at one end by an electrically conducting cap portion electrically connected to a layer of the laminate and a casing portion,

wherein the step of providing the casing portion comprises: [0445] providing a first portion part with a first opening, the first opening opening into the cavity, [0446] providing a first material on the first portion part, the first material extending from the first opening, [0447] providing a second material on the first portion part and the first material and with a second opening at the first material, the second opening opening toward the surroundings of the battery.

[0448] 55. A method of venting gas from an inner cavity of a battery, the method comprising venting the gas to surroundings of the battery via a vent element formed in a wall part of the battery, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward the surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

[0449] 56. A method according to embodiment 55, wherein the battery further comprises a solid, gel or liquid material with a predetermined melting or evaporation temperature in the interval of 85-120° C., the material being positioned in the channel, the method comprising the step of heating the material to above 85 degrees.

[0450] 57. A method according to embodiments 56, wherein the battery further comprises one or more reservoirs provided in the wall part, each reservoir having a single opening, each single opening opening into the channel, and wherein the method comprises displacing material into at least one of the reservoirs during venting.

[0451] 58. A method according to any of embodiments 54-57, the method comprising: [0452] 1. providing a charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, [0453] 2. firstly folding or bending the laminate along or around a first axis, [0454] 3. Subsequently folding or bending the laminate along or around a second axis not parallel to the first axis, [0455] 4. providing the folded/bent laminate in a casing having a first and a second electrical terminal, [0456] 5. connecting the cathode layer to the first electrical terminal of the casing and the anode layer to the second electrical terminal of the casing.

[0457] 59. A method according to any of embodiments 54-58, the method comprising:

providing the casing having: [0458] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0459] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0460] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel,
positioning an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion,
providing a charge holding laminate in the cavity/channel, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer,
electrically connecting one of the anode layer and the cathode layer of the laminate to the cap portion,
closing the second end portion of the casing and electrically connecting the other of the anode layer and the cathode layer to an electrical terminal of the casing.

[0461] 60. A method of switching of a battery according to any of embodiments 48-53, when overheating, the method comprising:

providing the battery comprising: [0462] the end cap being a concave end cap, [0463] the casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing, [0464] a charge holding laminate in the casing, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, and [0465] a thermal switch comprising a connection portion, in electrical contact with one of the anode layer and the cathode layer, and a thermally reactive element configured to move the connection portion,
the method comprising: [0466] when the temperature is below a threshold temperature, the thermally reactive element positions the connection portion in a first position in electrical contact with the end cap in the cavity thereof and [0467] when the temperature is above the threshold temperature, the thermally reactive element positions the connection portion in a second position in which it has at least a predetermined minimum distance to the end cap so as to not be electrically connected to the end cap.

[0468] 61. A battery comprising:

a concave end cap,
a casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing,
a charge holding laminate in the casing, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, and
a thermal switch comprising: [0469] a connection portion electrically connected to one of the anode layer and the cathode layer and being configured to move between a first position and a second position, where, in the first position, the connection portion is electrically connected to the end cap within the cavity, and in the second position, the connection portion is at a at least a predetermined distance from the end cap so as to not be electrically connected to the end cap, and [0470] a thermally reactive element configured to position the end connection portion in the first position when the temperature is below a threshold temperature and in the second position when the temperature is above the threshold temperature.

[0471] 62. A battery according to embodiment 61, wherein the connection portion in the second position is closer to the laminate than in the first position.

[0472] 63. A battery according to embodiment 61 or 62, wherein the thermally reactive element is attached in relation to the casing at a position between the end cap and the laminate.

[0473] 64. A battery according to any of embodiments 61-63, wherein the thermally reactive element is configured to move the connection portion from the first position to the second position and back to the first position.

[0474] 65. A battery according to any of embodiments 61-64, wherein the laminate is folded or bent along or around at least two non-parallel axes and is provided in the casing and wherein cathode layer or the anode layer is connected to the end cap.

[0475] 66. A battery according to any of embodiments 61-65, wherein the casing has: [0476] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0477] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0478] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel, and [0479] an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion.

[0480] 67. A battery according to any of embodiments 61-66, the casing comprising an inner cavity closed at one end by an electrically conducting cap portion electrically connected to a layer of the laminate,

the battery further comprising a wall part and a vent element formed in the wall part, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.

[0481] 68. A method of switching of a battery when overheating, the method comprising: providing a battery comprising: [0482] a concave end cap, [0483] a casing having an opening closed by the end cap, the end cap having a cavity facing an inner space of the casing, [0484] a charge holding laminate in the casing, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer, and [0485] a thermal switch comprising a connection portion, in electrical contact with one of the anode layer and the cathode layer, and a thermally reactive element configured to move the connection portion,
the method comprising: [0486] when the temperature is below a threshold temperature, the thermally reactive element positions the connection portion in a first position in electrical contact with the end cap in the cavity thereof and [0487] when the temperature is above the threshold temperature, the thermally reactive element positions the connection portion in a second position in which it has at least a predetermined minimum distance to the end cap so as to not be electrically connected to the end cap.

[0488] 69. A method according to embodiment 68, further comprising the step of the themally reactive element being heated and moving the connection portion from the first position to the second position.

[0489] 70. A method according to embodiment 69, comprising the subsequent step of the thermally reactive element being cooled and moving the connection portion from the second position to the first position.

[0490] 71. A method according to any of embodiments 68-70, wherein the step of providing the charge holding layer comprises the steps of: [0491] 1. firstly folding or bending the laminate along or around a first axis, [0492] 2. Subsequently folding or bending the laminate along or around a second axis not parallel to the first axis, [0493] 3. providing the folded/bent laminate in a casing having a first and a second electrical terminal, and [0494] 4. connecting the cathode layer to the first electrical terminal of the casing and the anode layer to the second electrical terminal of the casing.

[0495] 72. A method according to any of embodiments 68-71, wherein the step of providing the casing comprises:

providing the casing having: [0496] a central portion having a cavity or channel with a longitudinal axis and a predetermined cross sectional area in a plane perpendicular to the axis, [0497] a first end portion adjacent to the central portion, the first end portion forming an inwardly extending shoulder, [0498] a second end portion adjacent to the central portion oppositely to the first end portion, the second end portion comprising an opening into the cavity/channel,
positioning an electrically conducting cap portion in the cavity/channel and adjacent to the shoulder portion,
providing a charge holding laminate in the cavity/channel, the charge holding laminate comprising at least an anode layer, a cathode layer and a separator layer provided between the anode layer and the cathode layer,
electrically connecting one of the anode layer and the cathode layer of the laminate to the cap portion,
closing the second end portion of the casing and electrically connecting the other of the anode layer and the cathode layer to an electrical terminal of the casing.

[0499] 73. The method according to any of embodiments 68-72, wherein the step of providing the casing comprises providing a casing comprising an inner channel or cavity closed at one end by an electrically conducting cap portion electrically connected to a layer of the laminate and a casing portion,

wherein the step of providing the casing portion comprises: [0500] providing a first portion part with a first opening, the first opening opening into the cavity, [0501] providing a first material on the first portion part, the first material extending from the first opening, [0502] providing a second material on the first portion part and the first material and with a second opening at the first material, the second opening opening toward the surroundings of the battery.
74. A method of venting gas from an inner cavity of a battery according to any of embodiments 61-67, the method comprising venting the gas to surroundings of the battery via a vent element formed in a wall part of the battery, the vent element comprising a channel having a first opening and a second opening, the first opening opening into the cavity, the second opening opening toward the surroundings of the battery and at least a portion of a length of the channel extending at least substantially in a plane of the wall part.