How Fast Do Elevated Temperatures Reach the Cell Interior?

Gerd Liebig, Pamina Bohn, NEXT ENERGY EWE Research Centre for Energy Technology, Germany

Lithium-ion batteries, which have a tendency to degrade at high temperatures, must adhere to stringent regulations guaranteeing their ability to withstand operating temperature fluctuations. Researchers at NEXT ENERGY used heat transfer modeling to study whether high welding temperatures can create enough temperature propagation within cells to cause irreversible damage, such as electrolyte decomposition and capacity loss. They discovered that tab welding can, in fact, induce irreversible damage, but laser welding is significantly less detrimental.

Simulated temperature distribution from tab welding at 1100°C after 4 seconds of thermal stressing (left) and 4 seconds after the heat has been removed (right).

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