My Powerwall was installed after Tesla added the self-signed certificate to the gateway, so I never had a chance to use this device handler. To get around the issue for now, I’ve created a SmartApp to access the Tesla server to get Powerwall info and allow commands. It’s not as ideal as accessing your local gateway, but I think it may be the only option right now without adding an intermediate proxy server. It also requires entering your Tesla server credentials, so again not as ideal as a direct gateway connection.
It’s still pretty beta, so use at your own risk if you want to help test it out.
The SmartApp code is available here: https://github.com/DarwinsDen/SmartThingsPublic/blob/master/smartapps/darwinsden/tesla-powerwall-manager.src/tesla-powerwall-manager.groovy
And the required Device Handler code is here: https://github.com/DarwinsDen/SmartThingsPublic/blob/master/devicetypes/darwinsden/tesla-powerwall.src/tesla-powerwall.groovy
Both the SmartApp and Device Handler code need to be installed before adding the smart app from the mobile UI Automation tab. Activating the smart app will also activate the powerwall device on the mobile app things tab.
Thanks @RLS for getting the ball rolling on this. I hope we can get back to the direct gateway connection method at some point. Also thanks to @trentfoley for your work on the excellent Tesla Connect app. It was very helpful to leverage the Tesla Connect app access token initialization code. Not sure, but it may make sense to bring Tesla Powerwall and vehicle code together at some point into a common smart app suite.