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I replaced my friends iPhone 6 battery but his other friend told him to buy the cheapest things. So now his phone is constantly running at half speed. It’s as if low power mode is on 24/7 but it’s worse cause it makes the phone lag a lot. Anyone else experience this.
I would say, poor quality battery. A new battery should fix this issue.
his other friend told him to buy the cheapest things is certainly a red flag! To be certain, use a battery utility, such as coconutBattery (for Mac) or 3uTools (for Windows). It will tell you what the health of the battery is. Anything less than 75% of design capacity will require replacement. EDIT
