(Pocket-lint) - Tesla and Mercedes-Benz are going toe-to-toe over something unrelated to cars.

Tesla shook up both the electric car and smarthome industries in April by unveiling the Tesla Powerwall battery, which can be placed at homes or in businesses in order to store solar energy. The device would allow people to be less reliant on the power grid as well as offer them a back up should that ever fail.

Now, Mercedes-Benz thinks it can do one better (or at least similar). The luxury car maker has unveiled a personal battery pack with cells that can store extra solar energy from your home's solar panels. Each pack stores 2.5kWh of electricity, but if you combine up to eight of them, you can reserve 20kWh.

Powerwall comes in 10-kWh weekly cycle and 7-kWh daily cycle models, but it's labeled as appropriate for both home and busienss use, so it's safe to say Mercedes' battery pack is as well. You'll be able to pick one up this September in Germany through subsidiary Accumotive (taking registrations now).

We're not sure how much it'll cost. Tesla's systems start at $3,500, so it'll be interesting to see how competitive Mercedes-Benz plans to get with pricing. Watch the video above for more details, if you understand German.

Writing by Elyse Betters.