Bosch GSR 7.2-1 Replacement Battery 7.2V 1500mAh

Bosch GSR 7.2-1 / GSR 7.2-2 — 7.2V Ni-MH Replacement Battery (2 607 335 437)

This is a 7.2V, 1500mAh Ni-MH battery pack for the Bosch GSR 7.2-1 and GSR 7.2-2 cordless drill/drivers. It replaces OEM part numbers 2 607 335 437, 2 607 335 587, BH-744, and B-8308. The pack slots into the GSR 7.2-1's base connector and restores power to a drill used for driving screws and drilling in wood, metal, and plastic.

• GSR 7.2-1 and GSR 7.2-2 compatibility: Both models share the same 7.2V flat-pack connector format and draw the same voltage rail from the base contact plate. Either pack will seat and lock identically — no connector or BMS handshake differences exist between these two drill variants.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on the GSR 7.2-1 platform. The Ni-MH cells accepted a full charge cycle without thermal shutdown, and the contact plate voltage read a stable 7.2V under load across repeated trigger pulls.
• Motor inrush run-in: On first use, run the drill at half torque for two full charge/discharge cycles before pushing it to maximum torque. This allows the pack's internal protection to profile the motor's inrush current spike before the drill sees sustained heavy fastening loads.

Voltage sag on the GSR 7.2-1 under sustained driving loads

Ni-MH cells at 7.2V have a flatter discharge curve than Li-ion, but they sag noticeably when the motor is held under continuous torque — driving long screws into hardwood, for example. That sag appears as reduced RPM and audible bogging even on a freshly charged pack. The root cause is internal cell resistance rising as current demand spikes past the motor's rated draw. If the drill bogs consistently, check the contact plate on both the tool and the battery for oxidation — resistance at that junction amplifies the sag effect significantly.

Charger not recognising the new pack after storage

Ni-MH packs can self-discharge below the charger's acceptance threshold during storage — typically below 6.0V on a 7.2V pack. When this happens, the Bosch charger may show no response or refuse to begin a charge cycle. Place the pack in the charger and leave it for 10–15 minutes — many Bosch chargers run a trickle pre-charge to recover packs below the main acceptance voltage. If the charger still shows no activity after 15 minutes, measure the pack voltage directly at the contact terminals: a reading above 5.0V means the pack can be recovered with a compatible Ni-MH trickle charger set to 0.1C (150mA for this 1500mAh pack).