Straight Talk Solar Z795G Replacement Battery 3.8V 2000mAh

Straight Talk Solar / Z795G — 3.8V Li-ion Replacement Battery

This 3.8V, 2000mAh Li-ion cell replaces the original battery in the Straight Talk Solar and Z795G smartphones. It fits the existing battery bay without modification and connects to the same charge IC and fuel gauge circuit. Capacity figure comes from the product specification — 2000mAh at 7.6Wh.

• Solar and Z795G compatibility: Both devices share the same battery bay dimensions (58.35 × 51.20 × 5.50mm), voltage rail, and connector pinout. The charge IC and BMS handshake protocol are identical across the two models, so one cell covers both.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the Z795G platform. The BMS accepted the charge handshake without fault flags, and the protection circuit tripped correctly at the low-voltage cutoff threshold — no runaway observed.
• Fuel gauge recalibration on first cycle: After installation, disable fast charging and run one full discharge-to-charge cycle before regular use. The fuel gauge IC carries calibration data from the old cell. A single slow cycle lets it map the new discharge curve before high-current charging pushes current into an uncalibrated cell.

Sudden shutdown at 20–30% on the replacement cell

This is a voltage cliff problem, not a capacity problem. Under modem transmission or screen-on load, the cell voltage drops sharply before the percentage shown suggests it should. The fuel gauge IC is still using the old cell's discharge curve, so it reports 25% when the actual cell voltage has already fallen below the BMS cutoff threshold. One full slow discharge-charge cycle recalibrates the coulomb counter and eliminates most of these early shutdowns. If shutdowns persist past two cycles, check that the connector is fully seated — a high-resistance contact causes voltage sag under load at the pin level.

Fast charging not working after the battery swap

On the first cycle after a cell replacement, the USB-PD negotiation or proprietary charging protocol may not activate. The charge IC runs an impedance check on the new cell before it steps up to high-current mode — a fresh cell with slightly higher internal impedance can cause the IC to stay in trickle mode. Plug in via the original cable and charger, leave it on charge for a full cycle without interrupting. By the second charge cycle, impedance normalises and fast charging typically resumes at the expected rate.