About this replacement
Bang & Olufsen Beocom 2 — 3.6V Ni-MH Replacement Battery (3HR-AAAU-2)
This is a 3.6V, 700mAh Ni-MH replacement battery for the Bang & Olufsen Beocom 2 cordless telephone handset. It matches the OEM part number 3HR-AAAU-2 and fits directly into the Beocom 2 handset battery compartment. Voltage and capacity match the original specification exactly.
- Beocom 2 handset fit: The Beocom 2 runs a 3.6V three-cell NiMH pack in a specific form factor — 43.65 × 19.70 × 19.70mm. The base station's charging circuit expects this voltage profile. A pack outside that window will either refuse to charge or trigger a fault indicator on the base.
- Bench tested on actual hardware: We cycled this pack through the Beocom 2 base station charging circuit and confirmed the NiMH charge acceptance curve matched the base station's trickle and top-off phases without triggering an error state.
- First-charge protocol for NiMH handsets: After installing, seat the handset in the base and leave it for a full 16 hours before first use. NiMH cells in cordless phones need a slow initial charge to reach rated capacity — cutting this short means the pack will underperform for the first several cycles.
Talk time shorter than expected after replacing the Beocom 2 battery
NiMH cells ship in a partially discharged state and need three to five full charge-discharge cycles before they reach rated capacity. On the first cycle, you may get noticeably less talk time than the original battery delivered at its peak. Each subsequent full cycle builds cell capacity progressively. By cycle five, the pack should be performing at or close to its 700mAh rating.
Beocom 2 base station showing no-charge or error light after battery swap
If the Beocom 2 base station shows a charge error or no charge indicator immediately after fitting a new battery, the pack voltage is likely below the base station's acceptance threshold from storage discharge. Remove the handset, wait 30 seconds, then reseat it firmly — this re-initiates the charge handshake. If the error persists, confirm the battery contacts on both the handset and base are clean and making full contact. A resting voltage below approximately 3.0V on a fresh NiMH pack is normal and should resolve after the base completes its first trickle-charge phase.