Shareholders voted in favor of Tesla buying SolarCity in a deal worth about $2 billion on Thursday, placing greater importance on Tesla's at-home battery.

Tesla unveiled its newly improved at-home battery, Powerwall 2.0, during its big solar-roof unveiling at the end of October.

The battery comes with incremental improvements from a technical and design standpoint. The rechargeable battery is meant to complement Tesla's new solar roof product that will be sold under the new Tesla-SolarCity umbrella.

Here's everything we know about Tesla's Powerwall: