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Then, why do we need a solid-state battery? It is to increase capacity of EV batteries and increase safety.
Safety
What users most worry about a lithium-ion battery is safety. The current Li-ion battery has a risk of battery damage such as swelling caused by temperature change or leakage caused by external force since it uses liquid electrolyte solution. Therefore, we need devices or components that can improve safety.
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However, a solid-state battery with solid electrolyte shows improved stability with a solid structure, and increased safety since it maintains the form even if the electrolyte is damaged.
Capacity
Market research companies expect that EVs will replace ICEVs(internal combustion engine vehicles), and become the mainstream in the auto industry. And to become the unarguable leader in the industry, EV should have the similar level of mileage as the current ICEV, and it is important to increase the battery capacity of an EV battery to do so.
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