Black & Decker 18V Cordless Trimmer Replacement Battery 244760-00

Black & Decker BDGL1800 Series — 18V Li-ion Replacement Battery (244760-00)

This 18V 4000mAh Li-ion battery fits the Black & Decker BDGL1800 cordless string trimmer and a wide range of 18V Black & Decker power tools sharing the same slide-pack form factor. It replaces OEM part numbers 244760-00, A1718, A18, HPB18, and HPB18-OPE. Voltage and connector match the original — the trimmer's motor controller sees no difference between this pack and the factory unit.

• BDGL1800 and HPB18 platform fit: These models share a common 18V slide-rail platform with the same terminal layout and BMS handshake protocol. Any tool on this rail accepts the same pack — the controller reads voltage and cell status the same way across all of them.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on an 18V Black & Decker trimmer platform. The BMS held communication with the charger correctly, cell balancing completed without error, and the pack delivered consistent voltage across the full discharge curve.
• Motor inrush break-in on first use: Run the trimmer at half throttle for the first two cycles before pushing it into dense grass or thick weed stems. This lets the BMS log the motor's inrush current signature and set its overcurrent threshold accurately — reducing the chance of nuisance cutoffs later.

BMS overcurrent trip on trigger pull in the BDGL1800

When a string trimmer motor starts from rest, it pulls several times its running current for a fraction of a second. A new pack's BMS hasn't yet learned the motor's inrush profile, so the protection circuit can interpret that spike as a fault and cut the output. This is especially common in cold conditions, where Li-ion internal resistance is elevated and the voltage drop during inrush looks more severe. The fix is progressive — start with light load passes and let the BMS accumulate a few cycles before running the trimmer at full depth through thick material.

Charger blinks red and won't accept the pack after storage

If the pack has sat discharged for several months, cell voltage can drop below the charger's acceptance threshold — typically around 2.5V per cell. The Black & Decker 18V charger reads this as a fault rather than a depleted pack and refuses to begin a charge cycle. Some chargers have a recovery or "wake-up" mode that trickle-charges at a low rate until cells reach 3.0V per cell, at which point normal charging resumes. If your charger doesn't recover automatically, use a compatible charger with a Li-ion recovery function, or check that pack voltage at the terminals reads at least 10V total before attempting a standard charge.