Tesla founder Elon Musk has unveiled a 'revolutionary' $3,000 battery which he claims can run an entire home for eight hours.
Musk introduced the Powerwall device at a press conference in California last night and said the technology could 'change the world'.
The device, which could be in homes by the end of summer, will be able to store electricity at night when it is cheaper.
It would then discharge this cheap electricity during the day in quantities large enough to be useful to homes and businesses.
The Powerwall is around three feet wide and four feet tall, weighs 220lbs, and can be installed either on an outside or inside wall of a home.
The 'daily use' version has a capacity of 7 kilowatt-hours, which is around a quarter of a home's daily usage.
According to tech site Mashable, a single, fully-charged Powerwall device would be able to meet a quarter of a home's energy needs on any given day.
However, it would likely last far less time than eight hours during the mornings and evenings, when homes use the vast majority of their electricity.
Musk said that the devices can be stacked together to provide more energy.
The system would let homeowners with solar panels or other sources of renewable energy easily store their energy at home, rather than the current model whereby they sell power back to energy suppliers as it is produced, then buy it again during peak times.
It could also let savvy consumers take advantage of power companies' lower rates during the night and use the cheaper, stored energy during peak periods.
According to tech site Mashable, Musk told attendees at the event: 'Our goal is to fundamentally change the way the world uses energy.
'It sounds crazy, but we want to change the entire energy infrastructure of the world to zero carbon.'
As well as the daily-use model, Tesla will also launch a 10 kilowatt-hour backup battery, designed to tide homes over during power blackouts, such as those caused by storms.
Marketing material for the device, published late Thursday on Tesla's website, says: 'Powerwall is a home battery that charges using electricity generated from solar panels, or when utility rates are low, and powers your home in the evening.
'It also fortifies your home against power outages by providing a backup electricity supply.
'Automated, compact and simple to install, Powerwall offers independence from the utility grid and the security of an emergency backup.'
Musk said that he hopes to sell hundreds of millions of the devices, which he touted as a vast improvement over currently-available models. In the past he has said such early batteries 'suck'.
He later added that the entire showcase had been powered by a huge array of Powerwall batteries.
By Yeon Choul-woong
