Daly BMS Warns Against Using Lead-Acid Chargers with LiFePO4 Batteries

Daly BMS, a company specializing in battery management systems, has cautioned users against employing lead-acid battery chargers with Lithium Iron Phosphate (LiFePO4) batteries. The company asserts that such combinations are dangerous and can result in permanent damage to the lithium cells, potentially leading to thermal runaway.

The primary conflict arises from differing charging methodologies. Lead-acid chargers typically utilize a continuous float charge and may incorporate a high-voltage desulfation mode. These methods are incompatible with LiFePO4 batteries, which require a precise Constant Current/Constant Voltage (CC/CV) charging algorithm. The excessive voltage from a lead-acid charger can trigger the LiFePO4 battery's Battery Management System (BMS) to shut down or, in severe cases, cause overheating.

Furthermore, the BMS within the LiFePO4 battery will actively resist the mismatched voltage from a lead-acid charger. This results in the BMS repeatedly activating its over-voltage protection. Consequently, the battery remains undercharged, and the lifespan of both the BMS and the battery is significantly reduced.

Daly BMS emphasizes the importance of using a dedicated LiFePO4 charger. Such chargers adhere to a strict CC/CV profile, cease charging entirely once the battery reaches full capacity without a float stage, and often include a 0V wake-up function to safely re-engage the BMS if it enters sleep mode due to deep discharge.