Vita Slim new battery problem

I just changed the battery in a PS Vita slim and presto everything worked fine as soon as connected . After a few days sleeping the Vita still seemed to have some charge and I installed a 16gb memory card and went through the prompts to switch over to card memory . The Vita then attempted to restart and glitched . Ever since the Vita will run fine when connected to power but won’t turn on when disconnected , all I get is a single green light pulse . Have tried all the resets , and the orange light comes on when charging, any help would be appreciated !