Buddy, just buy a replacement battery https://www.ebay.com/sch/i.html?_nkw=BL-5J
I looked, but TBH, not sure what to make of "genuine" and "OEM" claims for a battery for a 16–year-old device (or 10-year-old if you count compatible Lumias). Descriptions usually do not mention manufacture dates either.
I looked, but TBH, not sure what to make of "genuine" and "OEM" claims for a battery for a 16–year-old device (or 10-year-old if you count compatible Lumias). Descriptions usually do not mention manufacture dates either.