Bang & Olufsen Beocom 9500 Replacement Battery 6V 650mAh

Bang & Olufsen Beocom 9500 / 9600 — 6V Ni-MH Replacement Battery

This is a 6V, 650mAh Ni-MH replacement battery for the Bang & Olufsen Beocom 9500 and Beocom 9600 cordless telephone handsets. It slots directly into the handset battery compartment and restores power to units where the original cell has degraded. Capacity is 3.9Wh — identical to the factory-fitted cell specification.

• Beocom 9500 and 9600 compatibility: Both handsets share the same battery bay dimensions, voltage rail, and connector layout. A single cell format serves both models without modification or adapter.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on a Ni-MH compatible charger, monitoring voltage stability across the charge curve. The cell held voltage within expected Ni-MH plateau range throughout the discharge phase without premature dropout.
• Ni-MH conditioning on first install: Ni-MH cells in cordless phones are prone to voltage depression if the first cycle is shallow. On first install, run the handset down until the low-battery indicator fires before placing it back on the base — this prevents early capacity loss from the memory effect that Ni-MH chemistry is susceptible to under partial cycling.

Why the Beocom 9500 shows full charge but drops out mid-call

Ni-MH cells in cordless handsets don't use a fuel gauge IC — charge level is estimated by the base station using voltage and elapsed charge time. When a new cell is installed, the base station's internal charge timer is still calibrated to the old, degraded cell. This means it may stop charging early, delivering only a partial fill. The result is a handset that reads full on the indicator but cuts out under the load of active transmission. A full conditioning cycle — discharged to low-battery alert, then charged uninterrupted on the base — resets the charge timing to match the new cell's actual capacity.

Handset not powering on after the battery sat in storage

Ni-MH cells that have self-discharged below roughly 1V per cell can appear dead on installation — the handset shows no response and the charging indicator may not activate. This is a deep-discharge state, not a failed cell. Place the handset on the base for at least 30 minutes before attempting to power it on; most Beocom base stations trickle-charge at a low current that can recover a deeply discharged Ni-MH cell. If the handset still shows no response after 30 minutes, remove the battery, measure cell voltage with a multimeter, and confirm it reads above 4.5V total before reinserting.