Why are most lithium batteries small in size

Why are most lithium batteries small in size

The lithium batteries, cylindrical batteries, soft pack batteries, and square batteries we see generally have a handsome appearance and cannot find the large size of traditional lead-acid batteries. Why is this?

Due to high energy density, lithium batteries are often not designed with large capacity. The energy density of lead-acid batteries is around 40Wh/kg, while lithium batteries have exceeded 150Wh/kg. The increase in energy concentration has raised the demand for safety.

Firstly, a single lithium battery with excessively high energy can lead to uncontrollable heat generation and rapid internal reactions in the event of an accident. In a short period of time, excessive energy cannot be released, which is very dangerous. Especially when the development of safety technology and control capabilities is not sufficient, the capacity of each battery should be restrained.

Secondly, in the event of an accident, the energy enclosed by the lithium battery casing is beyond the reach of firefighters and fire extinguishing agents. They can only isolate the scene in case of an accident and allow the accident battery to react on its own until the energy burns out.