Mine have been in Cost Savings TOU mode the entire time, and typically go from 100% to 40% each day, then recharge the next day. I'm only at 100% for a few hours before the afternoon peak period. My feeling is regular cycling helps maintain the capacity.
Within first 6 months of usage- approx 38 cycles worth of energy discharged (but no deep cycling)
You go to the https://pw.ip.addr.net (replace with your 4 number IP address) first and log in to the Powerwall. Then you can use the API
Just 4 byte numerical IP address. Your browser is going to complain that it isn't secure and you will need to select the advanced option and the proceed option. You will then get a login dialog box. The email and password is what you setup it up with the first time, there's a forgot password open.
Thanks. Boy, at first I couldn't figure out what was going on after the IP got me to sign in, customer, PW, etc and the picture with the house, battery, solar, grid
/api/status gets you uptime and firmware version
A bit higher than most people report for new systems, but not much more. The consensus is that on average the start with 14kWh capacity. A reddit thread that did a tear down implies that they might have a capacity up to 17.9 kWh based on the number of battery cells and the cell type.
If one were Tesla, wouldn't it would make sense to develop a market for cells that don't meet the necessary performance specifications for venicles that need maximum power/weight? i.e. home batteries?
I found an Australian battery testing group that has been running accelerated life cycle testing. Their testing methodology is cycling the battery at 80% (90%-10% I think) charge three times a day at hot/cold summer and hot/cold winter levels. They issue reports every 6 months and the latest report from Sep/2021 says that the Powerwall2 chemistry is Lithium Nickel Manganese Cobalt and after 2110 of their extreme cycles they SOH, State Of Health, was at 79%.
