Detailed Thermal Characterization on a 48V Lithium-Ion Battery Pack during Charge-Discharge Cycles

TL;DR

This paper provides an experimental analysis of temperature distribution and thermal behavior in a 48V Lithium-Ion battery pack during charge-discharge cycles, emphasizing the importance of module-specific thermal assessment for cooling system design.

Contribution

It offers detailed thermal characterization data of a Li-ion battery pack during operation, highlighting the temperature variations across cells and modules, which is novel for thermal management insights.

Findings

External surfaces exhibit better convective heat transfer.

Middle cells reach maximum temperatures during cycles.

Temperature gradients increase with discharge cycles.

Abstract

This study experimentally investigates the temperature distribution and behavior of a 48V Lithium-Ion (Li-ion) battery pack during two charge-discharge cycles using 25 thermocouples. Results indicate that better convective heat transfer occurs at the external surfaces of the pack, while middle cells reach maximum temperatures. Differences are also observed in the behavior of the three modules. The discharge cycle shows a temperature rise of 5.8{\deg}C with a pack temperature gradient increasing from 1.3{\deg}C to 2.7{\deg}C. The study highlights the importance of assessing the thermal behavior of each module and the complexity of the Li-ion battery pack system. Findings on the battery cells, modules, and pack in the same study can provide valuable insights for designing efficient cooling systems for Li-ion battery packs.