Battery Communication Protocol: CAN Bus and RS485 Explained
Battery Communication Protocol: CAN Bus vs RS485
A battery communication protocol lets the BMS talk to inverters and controllers. CAN bus and RS485 are the workhorses; picking right avoids integration headaches.
Comparison
| Protocol | Strengths | Use |
|---|---|---|
| CAN bus | Fast, robust, multi-node | EV, industrial |
| RS485 | Simple, long distance | Telecom, solar |
| SMBus/I2C | Small devices | Portable |
Specification Tips
- Match the inverter’s supported protocol.
- Request the protocol document from your lithium battery manufacturer.
- For turnkey builds, see battery application solutions.
Frequently Asked Questions
Which is better, CAN or RS485?
CAN for speed and noise immunity; RS485 for simple, long-run polling.
Do I need comms at all?
For basic loads, voltage signaling may suffice, but comms unlocks SOC accuracy and protection.
Written by Karl at China Battery Technology. Request a quote.
