18V ZAPACK ZP93 Replacement Battery 4000mAh Li-ion

ZAPACK ZP93 / ZP97 — 18V Li-ion Replacement Battery

This is an 18V, 4000mAh (72Wh) Li-ion battery for the ZAPACK ZP93 and ZP97 cordless electric strapping tools. It fits the battery slot directly and communicates with the tool's BMS on the same voltage rail as the original pack. Capacity figures are taken from the product data — 4000mAh at 18V nominal.

• ZP93 and ZP97 compatibility: Both models run the same 18V battery platform with identical connector pinout and BMS handshake protocol. The tensioning motor and welding circuit draw from the same cell group, so one pack serves both tools without modification.
• Bench tested on actual hardware: We cycled this pack through full tensioning and heat-weld sequences on the ZP93. The BMS held cutoff thresholds within spec across repeated peak-draw events at maximum tension setting. No false trips on the weld trigger at full state of charge.
• Cold warehouse use: If the tool is stored below 10°C, bring the battery to room temperature before starting. The tensioning motor pulls a sharp current spike at maximum tension, and a cold cell sitting near the BMS low-voltage threshold will trip the cutoff before the strap seats fully.

BMS cutoff during the tensioning cycle on the ZP93

The ZP93 tensioning motor draws its highest current right at the end of the tension stroke — when the strap is at maximum load and the motor is near stall. At that point, cell voltage dips sharply for a fraction of a second. If the pack is below roughly 50% state of charge, or if the discharge curve is already steep, the BMS reads that dip as an undervoltage event and cuts the output. The result looks like a stalled or locked tool, not a dead battery. Charge the pack fully before high-tension work, and check that the battery contacts on the tool are clean and making firm contact — resistance at the terminal raises the voltage drop under load.

Charger shows a fault light on a new pack straight out of the box

Li-ion cells self-discharge slowly during storage and transit. If a new pack has been sitting long enough, cell voltage can fall below the charger's acceptance threshold — typically around 12–13V for an 18V pack — and the charger refuses to start a normal charge cycle, flagging a fault instead. This is a protection feature, not a defective battery. Some ZAPACK chargers will recover the pack automatically if you leave it connected for 10–15 minutes; the charger trickle-charges until the pack crosses the acceptance voltage, then switches to the main charge cycle. If the fault light clears and charging begins, the pack is fine. If it does not clear after 20 minutes, check the charger output voltage at the terminals — it should read above 19V on the charge pins.