Lithium-ion batteries have become the preferred power source for modern forklifts due to their higher energy density, faster charging, longer service life, and lower maintenance compared with lead-acid batteries. However, integrating a lithium battery into a forklift’s electrical and control systems requires more than simply supplying power through the main positive and negative terminals. Auxiliary pins (also called communication or signal pins) play a vital role in safe, efficient, and compliant operation. This article explains why lithium forklift batteries need to work with auxiliary pins, what those pins do, and best practices for their use.
Auxiliary pins are additional electrical contacts on a battery connector that carry signals rather than main power. They typically interface with the battery management system (BMS), vehicle controller, charger, and safety systems. Common auxiliary signals include State of Charge (SOC), State of Health (SOH), cell voltage and temperature data, precharge/control signals, enable/disable commands, and CANbus/serial communications.
Key reasons why auxiliary pins are necessary, it is because of safe battery management demand, proper charging control, accurate state estimation and fleet management, safe vehicle integration and interlocks, thermal management, compliance and diagnostics.
Auxiliary pins are essential for making lithium forklift batteries safe, reliable, and efficient. They enable the BMS to communicate critical information, control charging and discharging, support thermal and safety systems, and integrate with fleet management and diagnostics. Properly designed auxiliary connections and protocols not only protect equipment and personnel but also maximize battery life and operational uptime — the core reasons many operations choose lithium power for material handling.
Below is recommended battery plug that is always recommended for lithium forklift battery with auxiliary pins available.
Euro Din Connector(or called Forklift Charging Connector)
Auxiliary pins optional accessory:
