I've been flying with the Powersonic PSL-BTL-1290 Iron Phosphate battery for about 6 months now. Same size as a 9 AHr Lead Acid battery so it fits in a Dittel battery box. It's rated at 9 AHr but tested on a Western Radio battery tester it achieves 10.4 Ahr (which is what the battery is reporting.) I especially like that it can measure and report discharge rate so you can anticipate run time. You can give each battery a unique name so that when using the app, you can select your battery from the others on the line. I've set 2 of our club gliders up with these batteries and a number of club members are beginning to use them. The battery uses a TI Bluetooth system (as determined by the MAC address) and likely a TI Battery Management Unit. As reported it the measurement system seems to be quite accurate.

Danny Brotto
LS-8/18 "P6"