Overview
The JKBMS B2A8S20P is an active balance BMS for building and managing LiFePO4, Li-ion, or LTO battery packs. It supports built-in Bluetooth (Android/iOS) monitoring, RS485 communication (default), and active balancing at 2A to help equalize cell voltages during operation.
Key Features
-
Battery string support:
- Li-ion: 3S-8S
- LiFePO4: 4S-8S
- LTO: 6S-8S
- Active balancing: Active Balance (Full State On), balance current 2000mA (2A).
- Continuous current: 200A continuous charge current; 200A continuous discharge current.
- Peak discharge: maximum discharge current 350A (MAX 2min).
- Power supply mode: battery pack self-powered.
- Bluetooth: built-in Bluetooth; supports Android / iOS phone. Download the specified Bluetooth application and activate the BMS. Open the Bluetooth application and find the relevant serial number to check data.
- Communication interfaces: RS485 (default). Customized options: CANBUS / HEAT.
- Protections (six security protection): over charge protection; short circuit protection; over discharge protection; over current protection; all-in protection (cable drop or poor contact); over temp protection.
-
Smart energy working mode switching:
- Storage Mode: for transportation, storage, offline, or wireless transmission off mode; does not consume battery pack current.
- Charging activates Normal Working Mode: returns to normal working mode; protection, equalization, and communication functions return to normal.
- Standby Mode: in static state (no charge/discharge current and no equilibrium current), automatically enters standby after the set time is exceeded (1-30 days can be set).
- Shutdown: automatic shutdown voltage; automatically shuts down when a cell falls below the shutdown voltage.
For wiring/interface selection and configuration support (RS485/CANBUS/HEAT), contact https://tsolar.top/ or service@tsolar.top.
Specifications
| Model | B2A8S20P |
| Number of battery strings | 3S to 8S |
| Number of Battery Strings (Li-ion) | 3S-8S |
| Number of Battery Strings (Lifepo4) | 4S-8S |
| Number of Battery Strings (LTO) | 6S-8S |
| Wiring method / output | Same port / Common Port |
| Balance method | Active Balance (Full State On) |
| Balance current | 2000mA (2A) |
| Continuous current | 200A |
| Continuous charge current | 200A |
| Continuous discharge current | 200A |
| Maximum discharge current | 350A (MAX 2min) |
| Over charge protection current (ADJ) | 10-200A |
| Conductive resistance in main circuit | 0.3mΩ |
| Single cell voltage detection range | 0-5V; error <10mV over full operating range; typical error value <5mV |
| Single cell voltage range | 1-5V |
| Voltage acquisition accuracy | ±5mV |
| Support single cell voltage dropout detection | Yes |
| Total voltage detection range | 0-100V, <0.5%FSR (FSR = full scale) |
| Current sense shunt | -150A~300A, error <0.5%FSR |
| SoC estimation accuracy | Error <8% (operating conditions) |
| Battery remaining capacity | Error range is less than 8% |
| Total Cycle AH cumulative value | Half of the charge/discharge value |
| Over charge protection voltage | 1.2-4.35V Adjustable |
| Over charge release voltage | 1.2-4.35V Adjustable |
| Over discharge protection voltage | 1.2-4.35V Adjustable |
| Over discharge release voltage | 1.2-4.35V Adjustable |
| Over current detect delay | 2~120S Adjustable |
| Other interfaces (default) | RS485 |
| Other interfaces (customized) | CANBUS/HEAT |
| Bluetooth function | Bluetooth built-in; support for Android & iOS phone |
| Operating power consumption | <5mA (without communication) / 15mA (485/CAN) |
| Standby power consumption | <2mA |
| Temperature detection | -40~125°C |
| Quantity of temperature detection | 3Pcs |
| Operating temperature | -40~85°C |
| Storing temperature | -40~95°C |
| Temp protection | YES |
| Short circuit protection | YES |
| Coulomb counter | YES |
| Size | 153*136*18mm |
| Interface pin labels (as marked) | CAN/RS485: GND, CAN_H, CAN_L RS485: GND, RX, TX, VCC LCD: K-, K+, GND, B, A, VCC Markings: GPS; LCD (by default); CANBUS (need customization); Heat Function (need customization) |
Applications
- LiFePO4 battery packs (4S-8S), Li-ion battery packs (3S-8S), and LTO battery packs (6S-8S)
- Energy storage battery packs requiring 200A continuous current and active balancing
- Battery packs requiring Bluetooth monitoring and RS485 communication (default)
Details
Active-balancing BMS options in the JKBMS line are designed for multi‑string lithium battery packs and clean harness routing.
Built-in communication support helps you monitor pack status and tune settings from a compatible app or wired interface.
A layered internal layout highlights the control board, power components, and connector blocks inside the housing.
Connector labeling makes it easier to choose the right interface—RS485 by default, with CANBUS or heating options available.
Bluetooth monitoring provides quick access to pack voltage, current, SOC, and per-cell voltage readings.
In-app setup covers chemistry selection and calibration-style settings alongside real-time cell and pack telemetry.
Six core protection functions help safeguard the pack during charging, discharge, faults, and temperature events.
Power modes support storage and transport needs while returning to normal operation automatically when charging begins.
A spec table helps confirm string count, balance current, and interface options across available variants.
