A method for preparing a positive electrode active material and a positive electrode active material prepared by the method are provided. The method includes preparing a lithium composite transition metal oxide represented by Formula 1, and washing the lithium composite transition metal oxide with a cleaning liquid containing cleaning water and a surfactant. The cleaning liquid contains cleaning water in an amount of no less than 50 parts by weight and less than 400 parts by weight based on 100 parts by weight of the lithium composite transition metal oxide.

A lithium battery cell with an internal fuse component without any welded tabs present for conductance from the internal portion thereof externally to power a subject device is provided. Disclosed herein are lithium ion (liquid electrolyte) battery configurations utilizing thin metallized film current collectors as conducting tabs that provide full electrical conductivity from one pole to another throughout the internal portions of the battery with sufficient space for liquid electrolyte flow as well. Such thin metallized film current collectors thus provide both safety features with low electrical charge runaway potential, low internal resistance, and high thermal conductivity with a simplified manner of providing external electrical conductivity simultaneously.

An electrochemical device includes an electrode assembly. The electrode assembly includes a first electrode plate, a second electrode plate, and a separator disposed between the first electrode plate and the second electrode plate. The first electrode plate includes a current collector, a tab, and an active material layer. The active material layer includes a body region and an edge region. Widths of the edge region and the body region are W.sub.1 and W.sub.2 respectively, and 0<W.sub.1/W.sub.2≤5%. Thicknesses of the edge region and the body region are t.sub.1 and t.sub.2 respectively, and 95%≤t.sub.1/t.sub.2≤100%. The edge region falling with the foregoing parameter ranges helps to increase the energy density of the electrochemical device, reduce lithium plating hazards, and improve the safety of the electrochemical device.

This application provides a copper plating solution for a composite current collector, including a leveling agent represented by a general formula (1)

##STR00001## where an anion X is F.sup.−, Cl.sup.−, or Br.sup.−; R.sub.1, R.sub.2, and R.sub.3 are each independently selected from O or S; and R.sub.4, R.sub.5, and R.sub.6 are each independently selected from hydrogen, a substituted or unsubstituted alkyl, a substituted or unsubstituted vinyl, a substituted or unsubstituted aryl, and a substituted or unsubstituted heteroaryl.

The present disclosure provides a negative current collector (10), a negative electrode plate (20), an electrochemical device, and an apparatus. The negative current collector (10) includes a support layer, and a conductive layer (102) disposed on at least one of two opposite surfaces of the support layer (101) in a thickness direction of the support layer; wherein the support layer (101) has a smaller density than the conductive layer (102); the conductive layer (102) has a thickness D.sub.1 satisfying 300 nm≤D.sub.1≤2 μm, preferably 500 nm≤D.sub.1≤1.5 μm; and when the negative current collector (10) has a tensile strain of 1.5%, the conductive layer (102) has a sheet resistance growth rate T satisfying T≤5%.

A cell system includes: a stacked-type cell module (100) having a plurality of lithium ion unit cells (1) being stacked and having through holes (3a, 3b) formed therein; a gas supply part (31); a cooling liquid supply part (32); a temperature sensor (35); and a control part (36) that controls switching between a normal control mode and a high-temperature control mode based on a signal from the temperature sensor (35). In the normal control mode, the control part (36) controls the gas supply part (31) to supply a gas to the through holes (3a, 3b), and at the same time, controls the cooling liquid supply part (32) to stop supply of a cooling liquid, and in the high-temperature control mode, the control part (36) controls the cooling liquid supply part (32) to supply the cooling liquid to the through holes (3a, 3b) to which the gas is supplied, and at the same time, controls the gas supply part (31) to stop supply of the gas. According to this cell system, the increase in temperature of the cell is suppressed while having a simple configuration with a reduced formation region of through holes provided in a lithium ion cell.

This secondary battery positive electrode is provided with a positive-electrode current collector, a positive-electrode mixture layer, and an intermediate layer disposed between the positive-electrode current collector and the positive-electrode mixture layer. The intermediate layer comprises: a first intermediate layer that includes a non-oxide conductive inorganic compound and a positive-electrode active material; and a second intermediate layer that includes an insulating inorganic material and a non-oxide conductive inorganic compound. The conductive inorganic compound becomes an insulating oxide at 300° C. or above.

Power sources that enable in-body devices, such as implantable and ingestible devices, are provided. Aspects of the in-body power sources of the invention include a solid support, a first high surface area electrode and a second electrode. Embodiments of the in-power sources are configured to emit a detectable signal upon contact with a target physiological site. Also provided are methods of making and using the power sources of the invention.

Power sources that enable in-body devices, such as implantable and ingestible devices, are provided. Aspects of the in-body power sources of the invention include a solid support, a first high surface area electrode and a second electrode. Embodiments of the in-power sources are configured to emit a detectable signal upon contact with a target physiological site. Also provided are methods of making and using the power sources of the invention.

According to one embodiment, a secondary battery including an electrode and an aqueous electrolyte is provided. The electrode includes a resin current collector. The resin current collector includes a resin matrix and an electro-conductive filler. The aqueous electrolyte includes water.