The inventor of the wind-up radio, Trevor Baylis, has died aged 80.
He is believed to have died of natural causes in his home on Eel Pie Island, in Twickenham, south-west London, on Monday morning.
David Bunting, who runs his company, Trevor Baylis Brands, said he had been ill for a long time and has no living relatives.
Mr Baylis, who was awarded a CBE for services to intellectual property in 2015, had been seriously debilitated, having suffered from Crohn's disease, he added.
Scotland Yard said his death is not being treated as suspicious and a file will be prepared for the coroner.
"Police were called by London Ambulance Service at 8.47am on Monday March 5 to reports of a man taken ill at an address in Eel Pie Island, Twickenham," the Metropolitan Police said in a statement.
"Officers attended and the man, believed aged in his 80s, was pronounced dead at the scene.
"Inquiries continue to trace and inform next of kin."
Mr Baylis developed the wind-up radio in 1992 for people in the Third World who do not have access to electricity or batteries.
He was well known for championing the rights of inventors and was often outspoken about intellectual property rights.
The inventor was awarded an OBE in 1997 for his radio design and met the Queen at Windsor Castle to receive his CBE in 2015.
Paying tribute to his colleague, Mr Bunting said: "He made an enormous difference as the sole inventor in this company and did a tremendous amount to publicise their role and the importance of the inventions."
Speaking of Mr Baylis's CBE for his work with the patent office, he added: "He was always held in very high regard by them."