The battery used to be like this on A12 before A13 came in, then after the 1.5 OS update there have be tons of issue and non have been resolved related to battery, as mentioned I have giving feedback through the system and still there has been no action taken regarding the battery drain issue and now A13 welcomed some wakelok issues (Wakelok issues cause the device not to be able to go into deep sleep and cause idle drain issues), First wakelok was of Telephone Radio and RILJ ACK WL which was due to the internet through sim related and wasn’t fix and we still have them on A14
A14 also brought more wakeloks which are Wi-Fi related - qcom rx wakelock and NETLINK
There is not fix to this unless the developers team work on them and reduce them, I have attached the images of the 11k times wakelog they do in just 4hrs of phone usage and this is a huge issue cauing idle drain