A Perth tradie left fighting for his life after a robot vacuum exploded inside his home was caught in the blast after a leaking battery ignited while he was cooking, his mum has revealed.

Lachie Perrem suffered burns to 75 per cent of his body when the vacuum erupted inside his Brabham home on July 2, leaving him with catastrophic injuries and destroying the house he shared with his fiancee and housemates.

Now, for the first time, his mother Fiona Perrem has shared what she believes happened in the terrifying moments before the explosion.

“He had a robo vac and unbeknownst to him the battery had a leak,” she told the Daily Mail.

“When he started cooking something ignited and caused an explosion. He was at the forefront of it all.”

The cause of the explosion remains under investigation, with the robotic vacuum seized by the Department of Local Government, Industry Regulation and Safety for examination.

Mr Perrem has had three major operations, including skin grafts and wound debridement, after spending days in an induced coma.

But there has been a positive breakthrough in his recovery.

In an update on the family’s GoFundMe page, Ms Perrem said that her son’s feeding tube had been removed — another significant milestone in his long recovery.

“His grafts are healing well and the physio team is extremely happy with his progress, especially with the movement in his hands,” she wrote.

“His face and neck are healing really well too.

“Every step forward is a huge achievement, and we’re so grateful for the incredible care he’s receiving and for everyone’s ongoing support, encouragement and donations.”

Mr Perrem woke from an induced coma earlier in July and started communicating with his family and medical team after initially being unable to speak.

The explosion ripped through the family’s rental home, blowing out windows, blackening walls and leaving the kitchen and living room in ruins.

The family’s GoFundMe has now raised more than $44,400 to help cover Mr Perrem’s living expenses, rehabilitation and ongoing recovery while he remains in Fiona Stanley Hospital.