About this replacement
Texas Instruments TI-Planet / TI-Nspire Navigator Wireless Cradle WiFi — 3.7V Li-ion Replacement Battery (3.7L1750BPC)
This is a 3.7V, 1800mAh Li-ion replacement battery for the Texas Instruments TI-Planet calculator and the TI-Nspire Navigator Wireless Cradle WiFi. It replaces OEM part number 3.7L1750BPC. Use this when the original cell no longer holds a charge or the device fails to power on.
- TI-Planet and TI-Nspire Navigator compatibility: Both devices share the same 3.7V single-cell Li-ion power rail and use the same connector pinout and BMS handshake. One battery covers both units without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the TI-Nspire Navigator cradle. The BMS accepted the cell without fault codes, and voltage stabilised at 4.18V at full charge — within the expected range for this chemistry.
- RAM data export before swap: Export or photograph all stored programs and variables before removing the old battery. The TI-Planet stores user data in RAM that runs directly off the main cell. Pulling the battery without backing up first wipes everything — OS settings, programs, and saved variables included.
TI-Planet losing stored programs after a battery swap
The TI-Planet holds user programs and variables in volatile RAM. That RAM is powered by the main Li-ion cell — not a separate backup cell. The moment voltage drops to zero during a swap, RAM state is lost. There is no recovery path once the old cell is out and data is gone. Back up via TI-Connect CE or a USB cable to a PC before removing the battery.
Display reading low battery on a freshly installed cell
Replacement Li-ion cells ship in storage mode, typically at 3.6–3.7V — below the threshold the TI-Planet firmware uses to flag a healthy charge. The low-battery indicator is triggered by voltage, not actual capacity. Plug the device into a charger and let it complete a full charge cycle to 4.2V. The warning clears once the cell reaches operating voltage.