About this replacement
Panasonic ES7101 / ES6002 Series — 1.2V Ni-MH Replacement Battery (WES7038L2506)
This is a 1.2V, 2000mAh Ni-MH replacement battery for Panasonic cordless electric shavers. It fits the ES7101, ES7102, ES7109, ES6002, and over 40 additional Panasonic shaver models. Voltage and capacity match the OEM cell that Panasonic installed at the factory.
- ES7101 / ES6002 platform fit: These models share the same motor voltage rail, cell form factor, and BMS handshake protocol — 61.80 × 14.10 × 14.10mm with a 1.2V nominal output. Swapping in a mismatched cell trips the charge circuit before the battery reaches capacity.
- Bench tested on actual hardware: We cycled this cell through the shaver's charge dock and monitored BMS behaviour at full draw. The protection circuit accepted the cell without fault codes, and charge termination fired at the correct delta-V peak.
- Charging port care after wet shaving: Dry the charging port completely before docking the shaver. Water trapped between the charging contacts bridges them electrically — the BMS reads this as a fault and refuses to charge, which looks like a dead battery rather than a moisture issue.
Capacity fade from daily partial charging on Panasonic shavers
Ni-MH cells in shavers suffer voltage depression when recharged daily before the cell is meaningfully depleted. The battery's charge indicator drifts over time — it shows full but the usable window shrinks. This happens because partial cycling prevents the cell from fully resetting its electrochemical baseline. Running the shaver until the low-battery indicator activates before recharging slows this drift considerably.
Motor speed drops before the low-battery indicator activates
This is voltage sag under motor load, not a faulty indicator. When a Ni-MH cell ages, its internal resistance rises — the motor draws current faster than the cell can sustain voltage, so the shaver slows before the BMS reaches its cutoff threshold. The indicator is measuring resting voltage, not loaded voltage, so the two readings diverge. If motor speed drops noticeably during a shave while the indicator still shows charge remaining, the cell has reached end of service life and the resting voltage will typically sit below 1.0V under load.