A Victoria couple had a huge scare when a backup battery for their home alarm system, they didn't even know was there, overheated to the point where it could have caused a fire. 

The battery, tucked away in a closet in their three-month-old baby's room, was also releasing what they believed were toxic fumes.The smell eventually caused them to check the closet.

"Neither us really knew there was a backup in there," said Marilyn Aubin, "And if we had known we didn't know it would be a concern. Now it makes me think our phone has a backup battery. What kind is that?" 

When the smell led them to it, the Aubins tried to remove the battery from their Price's Alarms system, but it was too hot to touch. They then called the fire department, concerned about the well being of their three-month-old baby.

Home alarm

Tucked away in a closet, the backup battery for the Aubins home alarm system was quietly overheating. The smell gave it away, but when the Aubins tried to remove it, it was too hot to touch. (CBC)

"They were concerned about it too," recalls Marilyn. "They said someone should come check it. They were worried if you put another battery in whether it would happen again."

The Aubins were out of their home for four days until the fire department told them it was safe to return. 

Price's Alarms has offered to come check it out, but the family declined the offer.

"We've been in the security industry over 100 years and we can't know for sure but I have never seen this with an alarm panel," said Kevin Price, vice president of operations for Price's Alarms.

An online search reveals a number of complaints about backup batteries getting hot, but no examples as extreme as what the Aubins say happened. These sort of batteries should be changed every three to five years.

The Aubins had theirs for seven.

Battery expert Darcy Van Kempen Seket says it's not an uncommon problem.

"Batteries can become discharged just by sitting, then when they get charged they can bulge and heat up."

The Aubins say the fumes were making them sick.

They are now searching for compensation from the company, but also want alarm users to know the risk associated with these backups.

The company hasn't yet provided compensation for hotel stays and the dry cleaning needed to remove the smell from their clothes, but it says they are still negotiating with the family. 

With files from Richard Zussman