Atlas Copco LokTor P12P 12V Compatible Battery 3300mAh Ni-MH

Atlas Copco LokTor P12P / S12P Series — 12V Ni-MH Replacement Battery

This is a 12V, 3300mAh Ni-MH replacement battery for the Atlas Copco LokTor P12P, P12T, S12P, and S12T cordless screwdrivers, plus eleven additional LokTor variants. It fits the original battery slot and connects to the same charging circuit these tools use in production and assembly environments. Capacity is 3300mAh (39.6Wh) — matched to the product data, not estimated.

• LokTor P and S series compatibility: The P12 and S12 variants share the same 12V battery rail, connector format, and BMS handshake protocol. One replacement battery covers both lines without modification or adapter.
• Bench tested on actual hardware: We cycled this pack through repeated trigger-pull sequences on the LokTor platform. The BMS held within spec on motor-start inrush and recovered cleanly between fastening cycles. No false overcurrent trips were recorded during testing.
• Assembly-line cycle care: In high-cycle production use, avoid hot-swapping directly from a warm charger into continuous fastening runs. Let the pack rest two minutes after charge completion — Ni-MH cells in an enclosed tool housing accumulate heat faster than the chemistry dissipates it, which compresses effective cycle count over time.

BMS cutoff on LokTor motor-start inrush surge

The LokTor P12P and S12P use compact motors with high inrush current on trigger pull — particularly under torque load. If the battery has sat in storage or been shallow-cycled repeatedly, internal cell resistance rises. That resistance increase amplifies the voltage drop at trigger pull, pushing the current spike above the BMS overcurrent threshold. The BMS trips the pack off as a protective response, not a fault. Running two full discharge-recharge cycles before returning the pack to heavy fastening use lowers internal resistance and stabilises the inrush response.

Tool bogs under load but runs normally at no-load speed

This is a voltage sag symptom — the pack voltage drops sharply when the motor draws current under torque, even though the tool spins freely with no fastener engaged. The most common cause is elevated contact resistance at the battery rail, either from worn contacts or oxidation on Ni-MH terminals after storage. Clean both the tool contacts and battery terminals with a dry cloth, then check rail seating. If sag persists after cleaning, measure pack voltage under load — anything below 10.8V under moderate torque indicates cell degradation and the pack needs replacement.