About this replacement
Amazon Kindle 6 / Kindle 4 Series — 3.7V Li-Polymer Replacement Battery (MC-265360)
This is a 3.7V, 750mAh (2.78Wh) lithium-polymer cell for the Amazon Kindle 6, Kindle 4, and Kindle 4G e-readers. It matches OEM part numbers MC-265360, 515-1058-01, and M11090355152. If your Kindle no longer holds a charge or fails to power on, this cell replaces the original.
- Kindle 4 and Kindle 6 compatibility: Both generations share the same 3.7V Li-Polymer form factor, connector pinout, and BMS communication protocol — one cell fits the full range of D01100-series boards without modification.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on a Kindle 6 unit. The BMS accepted the cell on first connection, reported state-of-charge correctly, and held voltage above 3.5V through a sustained e-ink workload.
- Post-swap charge cycle: After installing this cell, connect the Kindle to a USB charger and run a complete charge before use. The Kindle firmware recalibrates its battery percentage display against the new cell during that first full cycle — skipping it causes the percentage indicator to read incorrectly for days.
Why the Kindle 6 shows "Low Battery" immediately after a new cell is installed
Li-Polymer cells ship in storage mode, typically sitting between 3.6V and 3.7V — below the firmware threshold the Kindle treats as "charged." The device reads that resting voltage, flags it as low, and may refuse to boot past the USB charge screen. This is a voltage floor issue, not a faulty cell. Connect to USB power for at least 10 minutes and the Kindle will boot normally once the cell clears the minimum boot threshold.
Battery percentage jumping or freezing after a cell swap
The Kindle's fuel gauge IC learns cell characteristics over one or two full charge-discharge cycles. A brand-new cell has no learned profile, so the reported percentage can jump from 40% to 80% or freeze at a fixed number mid-use. This is firmware recalibration, not a hardware fault. Run two complete charge cycles — USB charge to 100%, use until the device warns low — and the percentage display will stabilise.