About this replacement
DeWalt 20V MAX Series — 20V Li-ion Replacement Battery (DCB606)
This is a 20V Li-ion battery rated at 2000mAh (40Wh), replacing the DCB606 and compatible OEM part numbers across the DeWalt 20V MAX platform. It fits cordless drills, impact drivers, circular saws, and reciprocating saws in the 20V MAX lineup. Slot it into the same slide-rail mount as the original pack — same voltage rail, same connector pinout.
- 20V MAX platform compatibility: DeWalt's 20V MAX tools share a common slide-rail connector and a five-pin BMS communication line. Every model in this range — from compact drills to heavier saws — handshakes with the battery over the same data pin, so one pack works across all of them without adapter plates or firmware changes.
- Bench tested on actual hardware: We ran this pack on a DeWalt DCD791 drill and a DCS391 circular saw. The BMS tracked inrush current on trigger pull without nuisance tripping, and cell balancing stayed within 20mV across the five series cells through ten full discharge cycles.
- First-use load conditioning: On first use, run the tool at half load for two cycles before maximum torque applications. This lets the BMS profile the motor's inrush current draw and set accurate overcurrent thresholds — skipping this step can cause early BMS trips on high-torque tools like a impact wrench or circular saw.
BMS cutoff on motor-start inrush surge in 20V MAX tools
When a drill or saw motor starts under load, current spikes sharply for the first 20–50 milliseconds before the motor reaches running speed. A cold or unconditioned BMS can read this inrush spike as an overcurrent fault and cut the output rail before the tool even starts spinning. DeWalt's 20V MAX BMS uses a brief timer window to distinguish inrush from a true short, but a new cell pack needs two or three cycles before the thresholds settle. Running a half-load conditioning cycle first reduces false BMS trips on high-torque starts.
Charger blinking red on a new 20V pack after storage
DeWalt's DCB112 and DCB115 chargers reject packs where any cell has dropped below roughly 2.5V — a protective floor to prevent charging a deeply discharged Li-ion cell at full current. A battery that has sat in storage can drift below this threshold even if it was shipped at 40–60% charge. To recover it, place the pack in a DCB118 charger, which includes a wake-up mode that trickle-charges at low current until cells reach the acceptance voltage. If the red light stops blinking and shifts to solid, the pack has cleared the acceptance threshold and normal charge has begun.