Many BMS boards have a TX/RX header. Using a USB-to-TTL adapter and a terminal program (like PuTTY or CoolTerm), you can send the command: AT+WTY=BATINFO Or in hex: 0xA5 0x02 0x01 0xA6 The BMS will return a structured string like: +WTY:BATINFO,CHK=Li-18650,Cyc=342,SOH=87%,Temp=28C,Warr=6M
: For refurbished or second-hand devices, it serves as a "Carfax for batteries," proving the actual health of the power unit regardless of the physical appearance of the device. How to Access (General) WTY-BatInfo
WTY-BatInfo – System Diagnostic Report Many BMS boards have a TX/RX header