Festool BPH9.6C Ni-MH Replacement Battery 9.6V 2100mAh

Festool BPH9.6C Series — 9.6V Ni-MH Replacement Battery (CDD9.6)

This is a 9.6V, 2100mAh Ni-MH replacement battery for the Festool BPH9.6C cordless drill/driver. It also fits models cross-referenced under part numbers CCD9.6, CCD9.6ES, and CCD9.6FX. The cell stack matches the original voltage rail and physical connector used across this Festool drill platform.

• BPH9.6C platform fit: The BPH9.6C, FSP-487512, FSP-488437, and FSP-490355 all share the same 9.6V sub-C cell stack, connector housing, and latch geometry — which is why one battery pack services the entire range without modification.
• Bench tested on actual hardware: We cycled this pack through three full charge-discharge cycles on the BPH9.6C platform. The Ni-MH cells held voltage across load transitions, and the protection circuit responded correctly to end-of-discharge cutoff without nuisance tripping.
• Ni-MH storage protocol for this drill: If the drill sits unused for more than four weeks, store the pack at roughly 40–60% charge. Ni-MH cells left fully charged in a warm environment develop voltage depression faster than cells stored at partial state of charge.

Voltage depression in Ni-MH packs under repeated shallow cycling

Ni-MH cells develop a voltage depression effect — sometimes called memory effect — when repeatedly discharged to only 30–40% depth before recharging. Over several cycles, the pack begins delivering lower terminal voltage under load, even though the charger shows a full charge. On the BPH9.6C, this shows up as reduced torque and slower clutch engagement. Running the pack through two or three deep discharge cycles — down to the tool's cutoff voltage near 8.4V — then fully recharging can partially restore usable capacity.

Drill cuts out immediately on trigger pull — not a weak pack

If the BPH9.6C cuts out in the first second of use rather than running weak, the cause is usually inrush current — the motor draws a spike well above running current the moment the trigger closes. On a pack that has been in storage, cell voltage may sit just above the charger's acceptance floor but drop sharply under that inrush load, tripping the protection circuit. Remove the pack, let it sit at room temperature for 20 minutes, then reconnect and trigger gently at half-pull for the first two uses. If cutout continues, measure pack voltage at rest — it should read at least 9.0V before load.