IUNI U2 32 GB battery

Hello ! I couldn't find gapps for the newest official ROM to my IUNI U2 32 GB, so i downloaded and installed custom ROM with gapps via bootloader, then my battery started to run low. Now it drains 1% battery per minute with screen turned on. I tried to install MIUI 5.9.4 but it doesn't want to apply and gets lagged on loading screen. If you could, please post a good ROM which doesn't drain battery so fast(with fitting gapps) or gapps to a newest official ROM. Android or miui I doesn't really care. I just need a good battery lifetime and play store. I tried almost 6 roms but none worked.
Thanks for help and sorry for broken language I'm still learning :angel: