Chosen Solution
As title says, I replaced the battery and the charger recently, the % is decreasing really slowly, any ideas?
Sadly the charing logic has a problem on your logic board. A common issue that causes this is using a cloned charger. Here’s a bit more: OEM MagSafe Chargers vs Cheap Imposters: Teardown for TruthDon’t Replace Your MacBook Charger With a Cheap KnockoffeBay scam, fake Apple MacBook charger, how to know a fake At this point you’ll need to find someone who has the skills to fix your logic board or as a last resort replace the logic board. Sorry for the bad news ;-{
