Chosen Solution
I purchased a replacement battery in August of 2019 for my old MacBook Pro. I installed and charged it used it a bit and let it sit, for about a year. I finally dusted it off and it was dead so I put it on the charger and coconut battery says it’s at 100% charge but battery status is “poor” and its charging with 0 watts. If I unplug it it immediately shuts off. I believe the battery is so discharged it can’t read it accurately. I tried smc and pram resets no luck. i then found the old battery and put it I , which read at one percent -and charged up fine. I tried placing the replacement battery back in and nothing has changed. Anyone have any ideas or do I just need to buy another ?
Sadly, I think you’ll need to get a new battery again. If you bought it from iFixit see if they will replace it under their warranty. When storing a system you want the battery no more than 1/2 charged and no less than 1/4.
