Provided is a lithium secondary battery having both visible light transparency and flexibility. A lithium secondary battery includes: a positive electrode film formed on a flexible transparent film substrate and capable of intercalating and deintercalating lithium ions; a transparent electrolyte having lithium ion conductivity; and a negative electrode film formed on a flexible transparent film substrate, the negative electrode film being a metal capable of forming an alloy with lithium or capable of intercalating and deintercalating lithium ions. When the positive electrode film contains a lithium source, the negative electrode film is made to have a thickness of 50 nm to 300 nm by using, as a negative electrode material, any of tin oxide, silicon oxide, titanium oxide, tungsten oxide, niobium oxide, molybdenum oxide, metal phosphide, metal sulfide, metal nitride, metal fluoride, or metal titanium composite oxide.

Disclosed are maleic anhydride-grafted cyclic olefin copolymers, methods for preparing maleic anhydride-grafted cyclic olefin copolymers, low temperature methods for laminating anodes comprising the maleic anhydride-grafted cyclic olefin copolymers, and anodes and alkali ion batteries that comprise the maleic anhydride-grafted cyclic olefin copolymers.

A positive electrode is provided with: a positive electrode current collector constituted of aluminum as the main component; a positive electrode mixture layer formed on the positive electrode current collector aid containing a lithium-containing transition metal oxide; and a protective layer interposed between the positive electrode current collector and the positive electrode mixture layer. The protective layer contains inorganic particles, a conductive agent, and a binder material. In the positive electrode, the peel strength between the positive electrode current collector and the protective layer is higher than the peel strength between the protective layer and the positive electrode mixture layer.

The present disclosure provides a current collector and a preparation method thereof and an application therefor. The current collector provided by the present disclosure includes a functional film layer and metal layers provided on an upper surface and a lower surface of the functional film layer, where the functional film layer includes a fire retardant. Due to an addition of the fire retardant in the functional film layer, the current collector and the preparation method thereof provided by the present disclosure can not only effectively decrease an ignition point, but also release the fire retardant from the current collector to an electrolyte at high temperature, so as to achieve an effect of active fire extinguishing and significantly improve a safety performance of a battery; the functional film layer can also carry the metal layers on the upper and lower surfaces thereon.

The present disclosure provides an electrode current collector for a lithium secondary battery, the electrode current collector comprising: two or more metal foil layers, and a resistive layer positioned between the two or more metal foil layers, wherein the resistive layer includes a volume expandable resin, a conductive material, and an adhesive, an electrode comprising the same, and a lithium secondary battery.

The present invention relates to a flexible lithium battery comprising a first current collector layer and a second current collector layer, wherein the first current collector layer has a first outer surface and a first inner surface, and the second current collector layer has a second outer surface and a second inner surface; there is a glue frame sandwiched between the first inner surface and the second inner surface to form a sealed and enclosed space, wherein there is an electrochemical system layer disposed in this sealed and enclosed space, with the electrochemical system layer comprising a first active material layer, a second active material layer, and an electrically insulating layer disposed between the first active material layer and the second active material layer; and there is a flexible adhesive layer disposed between the first inner surface and the first active material layer and/or between the second inner surface and the second active material layer, wherein this flexible adhesive layer consists of an adhesive and an electrically conductive additive, with the adhesive consisting of a linearly structured colloid and a stereoscopically structured colloid.

The present application relates to a positive electrode plate and an electrochemical device. The positive electrode plate includes a current collector, a positive active material layer and a safety coating disposed between the current collector and the positive active material layer, the safety coating including a polymer matrix and a conductive material, wherein the polymer matrix is fluorinated polyolefin and/or chlorinated polyolefin, and when the safety coating and the positive active material layer are collectively referred to as a positive film layer, the positive film layer includes Na ions and/or K ions at a content of 100 ppm or more, and has an absorption peak at 1646 cm.sup.−1 in infrared absorption spectrum. The positive electrode plate may improve safety performance at elevated temperature of the electrochemical device by quickly disconnecting the circuit at high temperature conditions or when an internal short circuit occurs.

Systems and methods are provided for a reaction barrier between an electrode active material and a current collector. An electrode may comprise an active material, a metal foil, and a polymer. The polymer (such as polyamide-imide (PAI)) may be configured to provide a carbonized barrier between the active material and the metal foil after pyrolysis.

The present disclosure provides an electrode assembly and a related battery, battery module, wherein, the electrode assembly includes: a plurality of first type of electrode plates and at least one second type of electrode plate which are arranged in a superimposing manner, the polarity of the first type of electrode plate is opposite to the polarity of the second type of electrode plate, the plurality of first type of electrode plates comprise a first electrode plate and a second electrode plate, wherein the first electrode plate comprises a first current collector, the second electrode plate comprises a second current collector, and the first current collector is different from the second current collector.

This application relates to a negative electrode plate, a secondary battery and apparatus thereof. The secondary battery of the present application comprises a negative electrode plate, the negative electrode plate comprises a composite current collector and a negative electrode active material layer disposed on at least one surface of the composite current collector, the negative electrode active material layer comprises a silicon-based active material, the silicon-based active material accounts for 0.5 wt % to 50 wt % of total mass of the negative electrode active material layer, and the composite current collector comprises a polymer support layer and a metal conductive layer disposed on at least one surface of the polymer support layer, and the composite current collector has a brittleness parameter C ranging from 0.03 to 0.5. The secondary battery and the negative electrode plate achieve good coordination between the current collector and the negative electrode active material layer.