About this replacement
NEC Dterm PS111 / PS3D / PSIII — 3.7V Li-Polymer Replacement Battery (0231004)
This 3.7V, 600mAh Li-Polymer battery replaces the original power cell in the NEC Dterm PS111, PS3D, and PSIII cordless handsets. It fits directly where the original sat, using the same footprint at 49.92 × 23.90 × 6.50mm. OEM part numbers covered include 0231004, 0231005, and NG-070737-002.
- PS111, PS3D, and PSIII compatibility: These three Dterm handsets share the same battery bay dimensions and 3.7V supply rail. The connector pinout and cell footprint are identical across the range, so one cell covers all three models without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a Dterm handset. The protection circuit tripped correctly at low-voltage cutoff, and the base station accepted a charge cycle without reporting a fault.
- First-charge procedure for Li-Polymer cordless handsets: Li-Polymer cells shipped at storage charge need a full uninterrupted charge before first use. Seat the handset in the base and leave it undisturbed until the charge indicator clears — pulling it off early during the initial cycle can set a false capacity ceiling in the handset's charge tracking.
Talk time shorter than expected after fitting a new cell
A fresh Li-Polymer cell rarely hits rated capacity on the first cycle. The handset's fuel gauge was calibrated to the old, degraded cell, so it misreads the new one low. Run two to three full charge-and-discharge cycles through normal use, letting the handset run down before returning it to the base each time. After three cycles, the gauge recalibrates and talk time stabilises near the rated 600mAh capacity.
Handset loses DECT pairing after battery replacement
Removing the battery cuts all power to the handset, including the memory that stores base station pairing data on some Dterm models. If the handset shows "no base" or fails to ring after a swap, the pairing has been lost. Re-register the handset from the base station menu — on most Dterm systems this is done by holding the registration button on the base for three seconds while the handset is powered on. The handset will reconnect once the base acknowledges the new registration.