Guide Overview

If a battery management system (BMS) and a smart charger both have communication functions, that does not automatically mean they can communicate correctly with each other. Compatibility depends first on the battery and charging requirements, then on the communication interface, protocol, message definitions and control behavior required by the system.

1. First Confirm the Battery and Charging Requirements

Before checking communication, confirm that the charger is electrically suitable for the battery. Provide the battery chemistry, exact number of cells connected in series (S count), target charging voltage and required charging current.

Nominal battery voltage alone is not enough to select the charger. Communication compatibility should be checked after the battery and charging requirements are confirmed.

2. Same Communication Interface Does Not Mean Compatible

A communication interface describes how devices connect and exchange signals. The communication protocol and message definitions determine what those signals mean and how the devices are expected to respond.

For example, two devices may both use Controller Area Network (CAN), but they still may not communicate correctly if they expect different messages or control behavior.

3. Confirm the Communication Protocol

Identify the communication protocol required by the BMS and charger. If protocol documents are available, provide them together with the exact device models and current configuration.

Do not assume that matching connector types or communication-interface names prove compatibility. The protocol, message definitions and required system behavior must also match.

4. Define What the BMS and Charger Need to Exchange

Depending on the system design, the charger and BMS may need to exchange information or commands such as charging permission, requested voltage or current limits, battery status, temperature information or fault status.

The exact data set and control behavior must be confirmed for the selected BMS and charger combination. The examples above should not be treated as functions automatically supported by every product combination.

5. Does a BMS Always Need to Communicate with the Charger?

Not always. The required architecture depends on the battery system and charger design. Some systems control charging through electrical charging limits without digital BMS–charger communication, while other systems require communication for charging control.

Confirm the intended charging architecture before selecting the BMS and charger. Do not add a communication requirement simply because both products offer a communication interface.

6. When Evaluating a DALY Smart Charger

DALY provides Smart Charger products for lithium-battery projects. The exact charger model and any required BMS communication or linkage should be confirmed for the specific battery system.

Do not assume that a DALY BMS and a DALY Smart Charger will automatically communicate simply because both products are from DALY. Compatibility still depends on the exact models, battery configuration and required communication/control behavior.

DALY Smart Charger product entry: https://www.dalybms.com/daly-charger/

7. If You Already Have a BMS and Charger

If the equipment has already been selected and you need a compatibility review or are troubleshooting communication, provide the exact BMS model, charger brand/model, battery configuration, charging voltage/current and available communication documentation.

If available, also provide the current BMS firmware/software version and describe the observed behavior. If the version is unknown, provide the product label or current configuration information available to you.

DALY can review whether the proposed combination uses compatible communication requirements and identify whether configuration, protocol adaptation or another product combination needs to be evaluated.

8. If You Are Selecting a New BMS and Charger

If the BMS and charger have not yet been selected, start from the battery and system requirements rather than from a communication-interface name.

Provide battery chemistry, exact S count, target charging voltage, required charging current, application, and whether the charger and BMS need to exchange data or control commands. If communication is required, specify the target behavior and any equipment the battery system must also communicate with.

DALY can use these inputs to evaluate candidate BMS and charger configurations and provide the relevant product and communication documentation for the project.

9. What to Send DALY

Battery: chemistry, exact S count, nominal pack voltage and capacity.

Charging: target charging voltage and required charging current.

BMS: exact model/series and firmware/software version if available; otherwise product label or available configuration information.

Charger: exact brand/model if already selected, or required charger specification for a new project.

Communication: required interface/protocol and protocol document if available.

System behavior: what information or control functions the charger and BMS need to exchange.

Observed issue: for an existing combination, describe what currently happens and what behavior is expected.

Commercial: sample, prototype, pilot or production quantity.

With these inputs, DALY's technical team can review the electrical and communication requirements, evaluate compatibility or a suitable new configuration, and provide the relevant documentation and quotation.

Frequently Asked Questions

Q1 — If both devices have CAN, will they communicate automatically? No. They must also use compatible protocols, message definitions and control behavior.

Q2 — Should I check battery voltage and charging current before communication compatibility? Yes. First confirm that the charger is electrically suitable for the battery, then verify communication requirements.

Q3 — Does a BMS always need to communicate with the charger? No. It depends on the charging architecture and system-control requirements.

Q4 — Will a DALY BMS automatically communicate with a DALY Smart Charger? Do not assume so. Confirm the exact BMS and charger models and the required communication/control behavior.

Q5 — What if I do not know the communication protocol? Send the exact BMS and charger information and any available product labels or documentation so the communication requirements can be reviewed before final selection.

Request a BMS–Charger Compatibility Review

If you already have both devices, send the BMS model, charger model, battery configuration, charging requirements, communication documents and the behavior you need checked.

If you are selecting a new combination, send the battery chemistry, S count, target charging voltage/current and required communication/control behavior.

DALY's technical team can review the project and provide the relevant configuration information, documentation and quotation.

Email: dalybms@dalyelec.com