About this replacement
Craftsman 315.11538 — 12V Ni-MH Replacement Battery (130279001)
This 12V, 2000mAh Ni-MH battery replaces part number 130279001 in the Craftsman 315.11538 cordless drill. It fits the 11538 platform and slots into the original charger and tool body without modification. Voltage and connector match the factory spec exactly.
- 315.11538 / 11538 platform fit: Both model numbers share the same 12V battery bay, slide-in connector, and charge-detection circuit. One battery covers either variant without adapters or wiring changes.
- Bench tested on actual hardware: We cycled this pack through repeated trigger-pull sequences and monitored the BMS response to motor-start inrush current. The protection circuit held within spec on each draw spike, and the charger handshake completed normally on every charge cycle we ran.
- Ni-MH break-in on the 315.11538: Run the drill at half load for the first two cycles before pushing it to full torque or sustained boring. This lets the BMS profile the motor's inrush draw and set its overcurrent thresholds accurately — skipping it can cause premature cutoffs on the first few hard trigger pulls.
BMS cutoff on the 315.11538 during motor-start inrush
When you pull the trigger on a cordless drill, the motor draws a current spike — sometimes four to six times its running load — in the first milliseconds of rotation. A fresh Ni-MH pack has a low state-of-charge baseline before break-in, and the BMS can read that spike as an overcurrent fault. The protection circuit trips and cuts output before the bit even bites into the material. Running two half-load cycles first charges the cells evenly and gives the BMS enough voltage headroom to ride through the inrush without tripping.
Charger not recognising the new pack after storage
Ni-MH cells self-discharge during storage, and if the pack sits long enough, cell voltage drops below the charger's acceptance threshold. The Craftsman charger checks for a minimum voltage on insertion — if it doesn't see it, the charge cycle never starts. To recover, briefly connect the pack to a known-good Ni-MH charger set to a trickle or conditioning mode to raise the cell voltage above the recognition floor. Once voltage climbs above roughly 1.0V per cell, the standard charger will accept the pack and begin a normal charge cycle.