About this replacement
Craftsman 315.22411 Series — 12V Ni-MH Replacement Battery (11102)
This is a 12V 1500mAh Ni-MH replacement battery for Craftsman cordless power tools, specifically the 315.22411, 315.224110, 9-27137, and 9-27139 models. It replaces OEM part numbers 11102 and 981078-001. The pack slots into the original battery port and powers drilling, driving, and fastening tasks at the same voltage as the factory cell.
- 315.22411 and 9-27137/9-27139 compatibility: These models share the same 12V rail, physical connector, and NiMH charging protocol. The BMS handshake is identical across the cluster, so one cell configuration covers all four fit models without adapters or modification.
- Bench tested on actual hardware: We cycled this pack through full charge and discharge on the 315.22411 platform. The BMS tracked cell temperature correctly, and the pack held voltage under simulated trigger-pull inrush without tripping overcurrent protection.
- NiMH break-in on first use: Run the tool at half load for two complete charge-discharge cycles before applying maximum torque. This allows the BMS to profile the motor's inrush current draw and set accurate overcurrent thresholds for full-load use.
BMS cutoff on motor-start inrush during trigger pull
When you pull the trigger on a 12V drill, the motor draws a current spike in the first 50–100 milliseconds that can be three to five times the steady running draw. If the BMS hasn't yet profiled this inrush pattern — common on a fresh or storage-recovered pack — it reads the spike as a fault and shuts down the output rail. The fix is two break-in cycles at reduced load so the BMS logs the real inrush signature. After that, full-torque trigger pulls clear without interruption.
Tool bogs under load and voltage drops mid-task
A pack that runs fine at low torque but bogs or slows under load is showing voltage sag — the cell's internal resistance is too high to sustain current at the motor's demand. On NiMH cells, this is accelerated by repeated shallow cycling, where the pack never fully discharges before recharging. To recover, run a full discharge-to-cutoff cycle followed by a complete charge. If the sag persists, check rail contact resistance at the terminal block — corroded contacts add series resistance and compound the drop. Target a resting voltage of 13.2–13.8V after a full charge before reuse.