About this replacement
Autel DS808 / IM508 / MK808K-BT Series — 3.7V Li-Polymer Replacement Battery (MLP5070111)
This 3.7V, 4250mAh lithium-polymer cell replaces the original MLP5070111 battery in Autel handheld diagnostic scanners. It fits the DS808, DS808K, IM508, MaxiCOM MK808K-BT, and 19 additional models in the same platform family. Dimensions are 103.50 × 69.50 × 4.00mm — match these against the cell you pull before ordering.
- DS808 / IM508 / MK808K-BT platform fit: These models share the same PCB layout, connector pinout, and BMS handshake protocol. The MLP5070111 part number spans all of them because Autel standardised the power rail across this scanner generation.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on the DS808 platform. The BMS accepted the charge curve without error flags, and the scanner completed a full OBD vehicle scan without voltage sag triggering a shutdown.
- Data export before swap: Export all saved vehicle profiles and diagnostic logs before removing the old battery. On Autel scanners in this series, vehicle data can be stored in RAM segments kept alive by the main battery — pulling the cell without exporting first risks losing that data permanently.
Why the DS808 won't boot after a battery swap
A freshly installed cell ships at storage charge — typically 30–50% state of charge. The DS808 boot sequence draws a short high-current pulse that a partially depleted cell can fail to sustain, causing the device to cut out immediately or not respond to the power button at all. This is a voltage threshold issue, not a fault with the battery or the scanner. Charge the replacement cell to full via the wall adapter before attempting to power on — the scanner's BMS will begin accepting charge even with the device off.
Wireless link dropping mid-diagnostic session
The DS808 uses a shared power rail for both the display and the wireless module. As the battery ages and internal resistance rises, voltage sag under combined screen-plus-wireless load can push the rail below the threshold the wireless module needs to stay connected. This appears as a dropped VCI link or Bluetooth disconnect — often while the battery indicator still shows 20–30%. Replacing the cell resolves the sag. After fitting the new battery, run a full charge cycle before your first live vehicle session to let the BMS calibrate the state-of-charge reading accurately.