Tesla has installed its 200,000th Powerwall, the company's home battery storage product, the company said in a tweet on Wednesday. Tesla's CFO Zachary Kirkhorn told investors during a first-quarter earnings call in April that Tesla is continuing to work through a "multi-quarter backlog on Powerwall," suggesting that the volume of installations will continue to soar in coming months. During that earnings call, Tesla CEO Elon Musk said the company will no longer sell its Solar Roof panel product without a Powerwall. ....