Continued from Kyocera to Roll Out New Li-ion Battery in 2020 (2)

The new battery does not require a process of cutting metal because it uses processed metal foil. The welding of the cell's external terminal is conducted after sealing each cell by using a plastic film and pouch processing. Therefore, metal pieces produced at the time of welding do not enter the cells. Also, many cells are combined to make a module after sealing the cells. So, metal pieces produced at the time of processing the metal case of the module do not enter the cells, either.

If a short-circuit should be caused in a cell, it would be insulated by the pouch material and would not affect other cells. The electrodes are fixed together with the separator by pouch processing and are hardly dislocated, according to Kyocera.

A prototype of the module of the new battery (source: 24M Technologies)

More material options might realize capacity density of 500Wh/kg

The new battery has a potential of improving capacity density because it enables to select electrolyte and active material from a larger number of options than existing batteries.

As for electrolyte, by placing solid electrolyte between the positive and negative electrodes, it becomes possible to select an appropriate electrolyte for each of the positive electrode's and negative electrode's active materials.

In the case of existing Li-ion batteries, electrolyte is injected so that it fills the space between the positive and negative electrodes. Because the same electrolyte is used for both of the electrodes, it is not possible to use, for example, a material that is excellent for the positive electrode but causes a side effect at the negative electrode.

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