1 General Description
TI's
BMS021 Battery Management System
(BMS) is an evaluation board for the
BQ7961X-Q1
family of devices
for use in large format lithium-ion battery pack applications to provide monitoring, protecting, balancing, and
communications. There are two variants of the evaluation board, the BQ79616EVM and the BQ75614EVM.
Each BQ79616EVM can manage up to 16 cells (80-V max) for Li-ion battery applications. Up to 35
BQ79616EVM modules can be stacked, for packs up to 560 series cells.
Each BQ75614EVM can manage 14 or 16 cells (80-V max) for Li-ion battery applications. The standalone
BQ75614EVM module includes integrated current sense.
Each system provides fast cell balancing, diagnostics, and module to controller communication. Independent
protection circuitry is also provided. Please see the
BQ79616-Q1
or
BQ75614-Q1
data sheet for more details on
each respective part.
Each EVM is equipped with precision measurement and synchronous communication to enable a master
controller to perform
State of Charge
(SOC) and
State of Health
(SOH) estimation. Highly-accurate cell voltages
and a fast sampling time for the entire battery pack allows more efficient operation of battery modules and more
accurate SOC and SOH calculations. Communication with stacked BQ79616EVMs is via an isolated daisy-chain
differential bus. For the standalone BQ75614EVM, SOC and SOH are further assisted by an integrated current
sense ADC.
Control a single EVM or multiple stacked EVMs using a PC-hosted GUI. Communication between the PC and
the base device in a stack of BQ79616EVM (or a single standalone BQ75614EVM device) is via a USB2ANY
UART interface. For a stack of BQ79616EVM devices, communication between all other EVMs in the stack
occurs via the isolated, daisy-chain differential communication bus. The PC GUI allows configuration of the
EVMs to monitor cells and other analog data channels, control balancing, and monitor details of any faults.
1.1 Key Features
This EVM includes the following features:
• Internal passive cell balancing
• Isolated differential daisy chain communications with optional ring architecture
• Flexible architecture for 6 to 16 cell applications
• UART interface
• High-accuracy cell voltage measurement
• Diagnostics
• 8 multipurpose GPIOs
• Resistor ladder to simulate cell voltages
• Supports Bus Bar Connection/Measurement
• High-accuracy current sense measurement (only available on the BQ75614EVM).
1.2 Key Electrical Parameters
The following table identifies the key electrical parameters:
Parameter
Value
Maximum battery pack voltage (stacked EVMs)
2400 V
Maximum operating voltage
80 V (depends on series R3, R4 value)
Minimum operating voltage
9 V (depends on series R3, R4 value, by default use at least 18V)
Maximum cell open circuit voltage
5 V
Ambient temperature
–40 °C to 105 °C
Nominal operating temperature
–20 °C to 60 °C
Cell balancing current
Approximately 200 mA @ 80 °C
General Description
6
BQ79616-Q1, BQ75614-Q1, and BQ79656-Q1 Evaluation Modules
SLUUC37B – JULY 2019 – REVISED OCTOBER 2020
Copyright © 2020 Texas Instruments Incorporated
