Mercedes-Benz is considering using old car batteries to power your house. The plan would see the German manufacturer rolling out a second-life program for its lithium-ion batteries to combat rival Tesla's Powerwall.
The plan is a solution to the increasing amount of unusable car batteries that will continue to build as EVs become a priority for more manufacturers. No longer suitable for use in cars once they degrade to 80 per cent of their original capacity - a process that can take as few as eight years - the premium manufacturer is investigating ways to use these still potentially very useful power-storage devices outside of the vehicle.
Leveraging research conducted by the Mercedes-Benz Energy company formed in 2016, the premium brand is looking to recycle used car batteries into power storage for residential and commercial buildings.
CEO of Mercedes-Benz Energy, Boris von Bormann, explains that just one vehicle’s battery bank would be capable of supplying enough energy to power an average-sized house in what he calls "second-life batteries".
“Stationary storage needs are for mostly renewable energy, so managing the intermittency and the time when renewable energies are produced - things like wind, solar, and others - so that way it can be distributed when it's actually needed,” Bormann said.
Mercedes is also planning to distribute the used batteries to its under-development fast-charging network, meaning drivers would be recharging their cars from batteries, rather than the grid.
“We're also looking at the automotive side, you probably need energy storage next to fast chargers, so that you have enough energy at that site or to mitigate some of the demand spikes.
“It's not very predictable in terms of when people are charging and fast charging. Then you have all the charges, all of a sudden, going at one time, and you see a huge demand spike. And a lot of utilities, they bill based on that demand spike, right? So you're gonna be in for a big charge because you have this demand. So a storage battery can then basically dispense against that peak to level that out.”
As battery technology continues to break new ground and storage capacity grows, Bormann’s plan is to hook up electric vehicles to homes, and into the grid.
For those lucky enough to have access to a free-charging station, you'd be able to charge your car all day and then go home and use that power to run your house.
“Basically you could use your vehicle to power your home. That's also something we're looking at in the future, but obviously your car would need to be there, or when you drove off your fridge would stop running, so that’s a little issue you have.
“Where you can actually make money is by trading the energy or the capacity that you have in the vehicle on an energy market and get a return on the investment on the capacity that you have in the car. And then, if there's power outages, you basically have a 100 kWh battery sitting outside that can power you at home.”
The German Powerwall competitor could also be available sooner rather than later, with Mercedes tipping electric vehicles will make up as much as 30 per cent of total new-car volume by 2025 and there's a huge internal push to put the ever-growing number of used batteries to work outside the car.
“It's not far, there are quite a few pilot projects going around the world, so it’s not even a handful of years away. the technology to do it is there now,” he says.
Bormann says Mercedes Energy is already in every market around the world, and it's "actively investigating” the Australian market.