An article on "PHEV, HEV, and EV Battery Pack Testing in a Manufacturing Environment" provides an interesting background on the issues involved in testing battery pack systems used in EVs (including the BMS).
Sample excerpt....
During BMS Development, engineers need a way to reliably test the BMS under real-world conditions to complete their verification and validation plans. Testing such as Hardware-in-the-Loop (HIL) is often performed at this stage. HIL testing involves simulating physical inputs and external digital connections to the pack while monitoring its outputs and behavior relative to design requirements.
It is not easy to accurately simulate all of the real-world conditions a BMS will be subjected to. But what does it cost you to skip testing over every condition? In the end, simulating nearly every combination of cell voltages, temperatures, and currents you expect your BMS to encounter is really the only way to verify that your BMS reacts as you intended in order to keep your pack safe and reliable.
Sample excerpt....
During BMS Development, engineers need a way to reliably test the BMS under real-world conditions to complete their verification and validation plans. Testing such as Hardware-in-the-Loop (HIL) is often performed at this stage. HIL testing involves simulating physical inputs and external digital connections to the pack while monitoring its outputs and behavior relative to design requirements.
It is not easy to accurately simulate all of the real-world conditions a BMS will be subjected to. But what does it cost you to skip testing over every condition? In the end, simulating nearly every combination of cell voltages, temperatures, and currents you expect your BMS to encounter is really the only way to verify that your BMS reacts as you intended in order to keep your pack safe and reliable.