Williams were forced to remove the Kers battery from Pastor Maldonado's car earlier this morning after the unit failed.
Firefighters surrounded the item as it was removed from the garage as a precaution, but the battery did not catch alight.
Mechanics are now replacing the part in order to allow the Venezuelan driver to take part in practice later this morning.
Williams had a Kers failure at the Spanish Grand Prix last year, which led to a garage fire that injured several members of the team.