ES2BMS

Ninebot ES2 BMS (battery management system)

Hardware

Whole bms is split into two separate boards, upper part is low-power and consists of

• ST STM8L151K6T6 MCU
• TI BQ7693003 Li battery AFE
• Ricoh R5434D40xA Li battery secondary protector (earlier models)
• 3x 1.5mm pitch double row 8 pin connector

Second part consists mostly of charge/discharge mosfets circuitry

Registers

Index	Size	Description
00	02	Magic 5A5A
10	0E	Serial number
17	02	Firmware version
18	02	Factory capacity
19	02	Actual capacity (this is not charge level !)
1B	02	Charge full cycles
1C	02	Charge count
20	02	Manufacture date
30	02	Status
31	02	Remaining capacity, mAh
32	02	Remaining capacity, %
33	02	Current, x10mA, positive - discharging, negative - charging
34	02	Voltage, x10mV
35	02	bTemperature1:bTemperature2, Deg C, 0 is -20
36	02	Balancing bitmap
3B	02	Health, %
40	02	Cell 1 voltage, mV
41	02	Cell 2 voltage, mV
42	02	Cell 3 voltage, mV
43	02	Cell 4 voltage, mV
44	02	Cell 5 voltage, mV
45	02	Cell 6 voltage, mV
46	02	Cell 7 voltage, mV
47	02	Cell 8 voltage, mV
48	02	Cell 9 voltage, mV
49	02	Cell 10 voltage, mV
51	02	Config straps?
70	0C	Activation data (MCU UID copy)

30 Status register

Bit	Description
0	config valid
1	battery activated
2	battery charge protection
3	chraging enabled
4	register write lock
5	is discharging
6	is charging
7	is charger inserted
8	discharge error
9	overvoltage detected
10	overheat
11	n/a
12	n/a
13	charge error
14	deep UV error
15	n/a