The discharge performance of a primary, bobbin-style electrochemical cell is improved by incorporating a separator formed from a continuous separator sheet defining a two-layer cylindrical sidewall and a closed bottom end between the included electrochemical cell cathode and anode. A first layer of the cylindrical separator is formed by rolling a first end of a continuous separator sheet into a cylinder having a central axis parallel with a longitudinal axis of the continuous separator sheet, and then rolling a second end of the continuous separator sheet around the exterior of the first cylindrical layer to form a second cylindrical layer. The closed bottom end is formed by a portion of the continuous separator sheet located between the rolled portion of the first end and the rolled portion of the second end.

An alkaline dry battery includes a bottomed cylindrical battery case; a positive electrode packed in the battery case and including n hollow cylindrical pellets; a negative electrode disposed in a hollow portion of the pellets; a separator interposed between the positive electrode and the negative electrode; and an alkaline electrolytic solution. The positive electrode includes manganese dioxide and a conductive agent, n is an integer of 1 or more, and an average density of manganese dioxide of the positive electrode is 2.80 to 3.00 g/cm.sup.3. The density d.sub.c of manganese dioxide in the center portion in the height direction of the positive electrode is 98% or less of an average value d.sub.e of density of manganese dioxide in each of both end portions.

An alkaline dry battery includes a bottomed cylindrical battery case; a positive electrode packed in the battery case and including n hollow cylindrical pellets; a negative electrode disposed in a hollow portion of the pellets; a separator interposed between the positive electrode and the negative electrode; and an alkaline electrolytic solution. The positive electrode includes manganese dioxide and a conductive agent, n is an integer of 1 or more, and an average density of manganese dioxide of the positive electrode is 2.80 to 3.00 g/cm.sup.3. The density d.sub.c of manganese dioxide in the center portion in the height direction of the positive electrode is 98% or less of an average value d.sub.e of density of manganese dioxide in each of both end portions.

An aqueous primary battery includes a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, and an aqueous solution electrolyte included in the positive electrode, the negative electrode, and the separator, wherein the negative electrode and/or the electrolyte includes an additive, the negative electrode includes a negative electrode active material, the negative electrode active material includes zinc, the additive includes a cyclic compound, and the cyclic compound has a first ring including a NCO structure, and a second ring that shares at least two atoms with the first ring.

A positive terminal of a battery may act as an antenna ground plane for communicating battery status information. The positive terminal of the battery may include a first electrically conductive external surface with a first surface area. The negative terminal of the battery may include a second electrically conductive external surface with a second surface area less than the first surface area. An antenna impedance matching circuit may electrically connect to a communication circuit, an antenna, and the positive terminal of the battery. Thus the positive terminal of the battery may act as a ground plane for the antenna.

A positive terminal of a battery may act as an antenna ground plane for communicating battery status information. The positive terminal of the battery may include a first electrically conductive external surface with a first surface area. The negative terminal of the battery may include a second electrically conductive external surface with a second surface area less than the first surface area. An antenna impedance matching circuit may electrically connect to a communication circuit, an antenna, and the positive terminal of the battery. Thus the positive terminal of the battery may act as a ground plane for the antenna.

A resin sealing gasket 10 to be incorporated in an alkaline battery 1 housing a power generation element (3 to 5) in a cylindrical battery can 2 closed at a bottom, the sealing gasket configured to insulate a top opening of the battery can and a negative electrode terminal plate 7 from each other. The sealing gasket includes: an outer periphery part 14 standing upward from the rim of a disc-shaped partition part 13; a boss part 11 in a hollow cylindrical shape enabling a rod-shaped negative electrode current collector 6 to stand at the center of the partition part; and a thin-walled portion 15 formed in a groove shape along the outer periphery of the boss part and being thinner than other portions of the partition part.

A resin sealing gasket 10 to be incorporated in an alkaline battery 1 housing a power generation element (3 to 5) in a cylindrical battery can 2 closed at a bottom, the sealing gasket configured to insulate a top opening of the battery can and a negative electrode terminal plate 7 from each other. The sealing gasket includes: an outer periphery part 14 standing upward from the rim of a disc-shaped partition part 13; a boss part 11 in a hollow cylindrical shape enabling a rod-shaped negative electrode current collector 6 to stand at the center of the partition part; and a thin-walled portion 15 formed in a groove shape along the outer periphery of the boss part and being thinner than other portions of the partition part.

A lithium battery includes a positive electrode designed as a hollow cylinder and defines a cavity, a negative electrode arranged in the cavity, a separator, a liquid electrolyte, a first current collector for the negative electrode, a second current collector for the positive electrode, an at least two-part housing that encloses an interior space in which the positive electrode together with the negative electrode arranged in the cavity and the separator are arranged, wherein a pin is provided as a first current collector inside the housing, a part of the housing serves as a second current collector, the pin has a first, terminal section embedded in the negative electrode and in direct contact with the negative electrode, and the pin has a second section not in direct contact with the negative electrode, and an insulator element that protects the second section at least partially against direct contact with the electrolyte.

Systems, apparatuses, and/or the like are provided. In some embodiments, an electrochemical cell may include a container, a ring-shaped cathode disposed within the container, wherein the ring-shaped cathode defines an open interior, an anode disposed within the open interior of the ring-shaped cathode, a separator disposed between the cathode and the anode, an electrolyte solution, and a current collector electrically connected with a portion of the container, wherein the current collector is positioned at least partially within the anode. For example, current collectors may include a base including a first material that is fixedly attached to the portion of the container and a zinc component composed of a second material and fixedly attached to the base.