Signs of a worn Hilti B22 battery
A Hilti B22 battery wears out gradually — first the runtime drops, then the tool loses power under load. Below you'll recognise the typical signs of wear and learn when a rebuild is worth it instead of buying a new pack.
The most common signs of wear
- Shorter runtime — one charge lasts less and less.
- Power drop under load — the tool bogs down when drilling or driving.
- Fast self-discharge — the pack loses charge even when left unused.
- Jumpy readings — the charge level leaps from full to empty.
- Heating up during charging or use.
Why a battery wears out
Li-ion cells have a limited number of charge cycles. Over time they lose capacity — this is normal wear, not a fault in the tool itself. Heavy use, cold and storing the pack discharged all speed it up.
When a rebuild is worth it
If the housing and contacts are sound and only the runtime has dropped, a rebuild restores full capacity. We replace all the cells with new ones (Samsung / LG / Sanyo) and reprogram the BMS — cheaper than a new pack, with a 12-month warranty and a 2–5 business-day turnaround.
When it's more than wear
If the battery won't charge at all, flashes an error, or jumps straight to full and shuts off, the cause is often the electronics (BMS) rather than the cells. We diagnose and repair that as part of the service too.
FAQ
- How do I know my Hilti battery can be rebuilt?
- If it used to work fine and only the runtime has dropped while the housing is intact, it almost certainly can. We confirm during diagnostics.
- Does shorter runtime always mean worn cells?
- Usually yes. Less often the cause is the electronics or contacts, which we assess before the rebuild.
- Is a worn battery dangerous?
- Heavily worn or swollen cells are better replaced. Noticeable heating of the pack is a sign to send it in for service.