Abstract: Lithium iron phosphate (LFP) batteries and nickel-cobalt-manganese (NCM) ternary batteries, the two exhibit different characteristics due to the differences in their cathode materials. Batteries with the same type of electrode material may also display diverse electrochemical and thermal behaviors due to different electrode constructions. The study explored the impact of discharge rates, operating temperatures and other factors on the electrochemical and thermal properties of the batteries, and comparatively analyzed the performance differences between LFP batteries and NCM batteries as well as batteries with varying electrode thicknesses. The results indicated that NCM batteries have superior high-rate discharge characteristics and better performance at low operating temperatures than LFP batteries. The heat generation characteristics of LFP and NCM batteries exhibit different sensitivities to ambient temperature, with LFP batteries showing an increase in heat generation as environmental temperature rises compared to NCM batteries. Batteries with thicker electrodes have a faster temperature rise rate than those with thinner electrodes. However, batteries with thinner electrodes exhibit better rate capability, with a smaller voltage drop after discharge rate increase compared to the batteries with thicker electrodes.

Key words: lithium-ion battery, electrode thickness, magnification performance, electrochemical