Battery storage fire and explosion in Mank house

What happened

On 15 September 2026 at about 20:30 a fire broke out in the cellar of a house in Mank, Bezirk Melk. The object involved was the battery storage of a photovoltaic installation, reported at about 27 kWh and made up of about 4,000 lithium-ion 18650 cells, in a former oil store that was also described as a fire-protected room and was hard for firefighters to reach. After crews entered, explosions were heard at about 20:50.

Equipment was damaged. One firefighter sustained a slight facial injury and another was taken for examination. Three residents were outside; two were given first aid and taken for checks, and all three remained uninjured. Firefighters flooded the room with water to cool the cells and stop smoke, and the cells were extinguished. The building was closed on the authority of the fire service and then the town mayor, and the network operator isolated the supply. Damage was reported in the six-figure euro range.

Contributing factors

Police fire investigation reported that energy from the photovoltaic system appeared to have overheated the cells because of a technical defect in the fuses, and that a chemical reaction and explosions in the cells may then have followed. Investigators also reported that a self-built store above 20 kWh must be checked by a licensed electrical contractor under the Lower Austria building rules, and that this had apparently not been done.

Lessons learned

1. Self-built battery storage above the local inspection threshold should be checked and accepted by a licensed electrical contractor before use.
2. Storage rooms should allow firefighters safe access, isolation and cooling without prolonged entry.
3. Protection on circuits feeding a battery bank should be verified so a fuse or connection fault cannot overheat cells.

Source

polizeiticker.at