About this replacement
Amazon Kindle Fire HD 7" — 3.7V Li-Polymer Replacement Battery (MC-347993)
This is a 3.7V, 3500mAh lithium-polymer cell replacing the original MC-347993 battery in the Amazon Kindle Fire HD 7" tablet (models SQ46CW, B00IKPYKWG, B00IKPW0UA). It fits the same physical footprint at 93 × 78 × 3.50mm and connects to the same charge IC on the mainboard. Capacity matches OEM spec at 12.95Wh.
- SQ46CW, B00IKPYKWG, B00IKPW0UA compatibility: All three Kindle Fire HD 7" variants use the same battery bay dimensions, the same 3.7V charging rail, and the same connector latch. One cell covers all three without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on a Kindle Fire HD 7" unit. The BMS accepted the cell on first connection, the charge IC recognised the correct chemistry, and the tablet completed a full charge cycle without fault flags.
- Fuel gauge recalibration after swap: After fitting this battery, run the tablet down to automatic shutoff — do not force-power it off. Then charge uninterrupted to 100%. This gives the fuel gauge IC a full reference cycle against the new cell and clears the inaccurate percentage readings that appear immediately after a swap.
Kindle Fire HD 7" shutting down at 15–25% remaining
This happens because the display backlight and active WiFi together pull enough current to cause a rapid voltage drop near the lower end of the cell's discharge curve. The fuel gauge IC — still calibrated to the old degraded cell — misreads the remaining capacity and triggers an early shutdown. Fitting a new cell alone does not fix this; the gauge still has stale reference data. Run one full discharge-to-shutoff followed by a full uninterrupted charge. After that cycle, the shutdowns at 15–25% stop.
Percentage jumping or dropping fast from 100% after battery replacement
The fuel gauge IC on the Kindle Fire HD 7" stores calibration data tied to the old cell's internal resistance profile. When a new cell goes in, the IC is reading the wrong map — so reported percentage drifts or drops faster than actual charge level. This is not a fault with the replacement cell. Charge the tablet fully, use it to automatic shutoff without interruption, then charge again to 100%. That two-point calibration resets the IC's reference curve to the new cell.