About this replacement
ZTE U110 / U116 / U118 Series — 3.7V Li-ion Replacement Battery (Li3710T42P3S543556)
This is a 3.7V, 1000mAh Li-ion replacement battery for the ZTE U110, U116, U116+, and U118 cordless DECT handsets. It replaces OEM part Li3710T42P3S543556 using the same slim 52.00 × 33.67 × 5.52mm form factor. Fit it when your handset no longer holds a charge or cuts out early during calls.
- U110 / U116 / U116+ / U118 compatibility: These four handset models share the same battery bay dimensions, connector pinout, and 3.7V supply rail. The BMS in each handset communicates the same charge profile to its base station, so one cell works across all four variants without firmware differences.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on ZTE DECT handset hardware. The BMS accepted the battery without error, held voltage within the expected 3.7V nominal range, and reported charge status correctly to the base station indicator.
- First-charge protocol for DECT Li-ion handsets: After fitting the battery, seat the handset in the base and leave it on charge undisturbed for a full 16 hours before first use. DECT base stations trickle-charge at a low current, and cutting that initial cycle short reduces the usable capacity the cell settles into long-term.
Talk time shorter than the original battery after replacement
A new Li-ion cell often underperforms for the first three to five charge cycles. The cell's internal chemistry hasn't yet reached full activation, so initial capacity reads lower than rated. Each full charge-discharge cycle conditions the electrodes and pushes available capacity closer to the 1000mAh spec. Run the handset down to low-battery alert, then return it to the base for a full charge — repeat this three times and talk time should stabilise.
Handset loses DECT pairing after battery swap
Removing the battery completely cuts power to the handset's memory, and some ZTE DECT models drop their base station pairing when that happens. The handset powers on but shows no line or fails to ring. To re-pair, hold the registration button on the base station until the LED flashes, then follow the handset's locate or register menu — typically found under Settings. Once registered, the handset resumes normal operation at full signal strength.