About this replacement
Einhell BT-CD 14 / MT-AS 14 Series — 14.4V Li-ion Replacement Battery (451317501014)
This is a 14.4V 2000mAh Li-ion replacement battery for the Einhell BT-CD 14 cordless drill-driver and MT-AS 14 multi-tool series. It slots into the same battery bay as the original and communicates with the same BMS handshake. Capacity is 2000mAh (28.8Wh), matching the original pack specification.
- BT-CD 14, 4/3 Li, MT-AS 14, 4 Li/2 compatibility: All four models share the same 14.4V rail, identical battery connector, and the same BMS communication protocol — that is why one pack covers all of them. Swapping between these tools requires no adapters.
- Bench tested on actual hardware: We ran this pack through repeated trigger-pull cycles on the BT-CD 14 and monitored the BMS overcurrent response. The protection circuit handled motor-start inrush without tripping, and cell voltage recovered cleanly between pulls.
- First-use load conditioning: On first use, run the drill at half load for two cycles before applying full torque. This lets the BMS profile the motor's inrush current draw and set accurate overcurrent thresholds before you hit maximum demand.
BMS cutoff on BT-CD 14 motor-start inrush surge
When you squeeze the trigger hard on a stalled or loaded bit, current demand spikes sharply for the first 50–100 milliseconds. A new or storage-depleted pack may have a conservative overcurrent threshold that reads this spike as a fault. The BMS cuts the output circuit to protect the cells. Running two partial-load cycles first teaches the BMS the actual inrush signature of this motor so the threshold calibrates correctly.
Charger not recognising the pack after sitting in storage
Li-ion packs left unused for several months can drop below the charger's acceptance threshold — typically around 10–11V for a 14.4V pack. When the charger sees voltage below that floor, it refuses to enter bulk charge mode and may blink an error. To recover the pack, check terminal voltage with a multimeter. If it reads above 10V, some Einhell chargers will accept a forced wake cycle by briefly seating and reseating the pack three times in quick succession — this prompts the charger to attempt a slow pre-charge pulse before normal charging resumes.