Battery

Information about the battery pack and BMS

Surface RT battery pack with exposed BMS circuit

Batteries are dangerous, working on one is difficult and require patience and skills! Do not disassemble, peel or remove one from the device unless you know what you're doing!

Specifications of the battery pack

Specifications

Title

Manufacturer

Samsung

Capacity

31.5Wh

Voltage

7.4V

Model number

P21GK3

BMS (Battery Management System)

A battery pack requires a reliable BMS. Without it you can't control and balance the cells, leading to fire hazards.

Overview
BMS
Cable
Overview
BMS
Cable

IC's marked with 1-3:

  1. ???

High resolution mock-up of BMS board

BMS board part 1
BMS board part 2
BMS board part 3
BMS board part 4
Cable
BMS board part 1
BMS board part 2
BMS board part 3
BMS board part 4
Cable

Macro shots of the various IC's

Chip 1
Chips 2
Chip 3
Chip 4
Chip 1
10 Amperes SFH Series Self Control Protector(SCP)
Chips 2
??? - Guessing both are balance chips
Chip 3
BQ28400 Netbook and Tablet Lithium ion gas gauge and protector
Chip 4
??? - Chip is unmarked, suspecting it's a temp probe logic