About this replacement
DT Research DT390 — 7.4V Li-ion Replacement Battery (ACC-006-18)
This is a 7.4V, 3600mAh lithium-ion battery for the DT Research DT390 rugged tablet. It replaces OEM part numbers ACC-006-18 and ACC-006-181. The DT390 is a purpose-built field tablet, and this battery powers its processor, display, and wireless radios.
- DT390 platform fit: The DT390 uses a fixed 7.4V cell configuration with a BMS handshake tied to the ACC-006-18 part family. This battery matches that voltage rail and connector pinout so the tablet's charge controller accepts the cell without throwing a fault.
- Bench tested on actual hardware: We cycled this battery through charge and discharge on the DT390 platform. The BMS passed authentication, the charge IC engaged without error flags, and cell voltage held stable across a full cycle.
- Fuel gauge reset after installation: After fitting this battery, run the tablet down to automatic shutoff, then charge it uninterrupted to 100%. This forces the fuel gauge IC to recalibrate against the new cell's actual capacity and corrects the inaccurate percentage readings that commonly appear after a swap.
DT390 shutting down at 15–25% battery remaining
The DT390 draws hard on the battery when the display is at full brightness and the wireless radio is active simultaneously. An aged or uncalibrated cell hits a voltage cliff under that combined load before the reported percentage reaches zero. The tablet's protection circuit reads the voltage drop as critically low and forces a shutdown. Running one full discharge-to-shutoff cycle recalibrates the fuel gauge IC and brings the cutoff point back in line with the actual state of charge.
Fast charging unavailable after battery replacement on the DT390
If the DT390 drops to standard charge rate after a battery swap, the charge IC needs one complete accepted charge cycle before it renegotiates higher-rate charging. This is a handshake behaviour — not a fault with the replacement cell. Plug the tablet into its original charger and let it run from low charge to 100% without interruption. After that first full cycle completes, fast charge availability typically restores on the next connection.