DeTeWe Tenovis Integral D3 Replacement Battery 2.4V 600mAh

DeTeWe Tenovis Integral D3 / Openphone 28 / OpenPhone 24 — 2.4V Ni-MH Replacement Battery

This is a 2.4V 600mAh Ni-MH replacement battery for the DeTeWe Tenovis Integral D3, Openphone 28, and OpenPhone 24 cordless handsets. It replaces the original rechargeable cell that powers the handset during wireless calls and standby. Dimensions are 35.80 × 33.50 × 7.00mm — confirm these match your existing cell before ordering.

• Integral D3, Openphone 28, and OpenPhone 24 compatibility: These three handsets share the same battery bay dimensions and 2.4V NiMH cell format, which is why one replacement cell covers all three models without modification.
• Bench tested on actual hardware: We cycled this battery through charge and discharge on a NiMH test rig. Capacity settled at rated output by cycle three, and voltage held steady through the discharge curve without early cutoff.
• First charge on NiMH cordless handsets: After installing, seat the handset in the base for a full 16-hour charge before first use. NiMH cordless phone batteries reach rated capacity through a slow initial charge — a quick top-up will not fully condition the cell.

Range dropping after a battery swap on the Integral D3

The Integral D3 handset adjusts its RF transmit power based on available voltage from the battery. A new NiMH cell straight from storage sits at a depressed open-circuit voltage — sometimes below 2.2V — which causes the handset to throttle transmit power and shorten usable range. This is not a fault with the replacement cell. After two or three full charge cycles, the NiMH pack recovers to its nominal 2.4V and the handset transmits at full power again.

Base station shows no charge light after fitting a new battery

Some DeTeWe base stations sample the battery voltage on contact and withhold charging current if the reading falls below their acceptance threshold. A new NiMH cell that has self-discharged in storage can read low enough to trigger this behaviour. Remove the handset, wait 10 seconds, and reseat it firmly — the base will re-sample and usually begin charging. If the error persists, check that the handset contacts are clean and that the cell is making solid contact with the battery terminals inside the handset.