If you got a battery replacement from a repair shop, it’s now eligible for official Apple repairs at Genius Bars and Apple Authorized Service Providers (via iGeneration).
[iOS 11.3: Understanding iPhone Battery Management]
Official Apple Repairs
Previously, Apple Store Genius Bars and Apple Authorized Service Providers were told to deny repairs for third-party batteries. Now, if the repair isn’t related to the battery your iPhone can get official Apple repairs.
When a repair happens the battery needs to be drained to less than 60% charge. If the battery tabs are broken or missing, or there is too much adhesive, Genius Bars and Apple Authorized Service Providers may replace the whole iPhone for only the cost of a battery replacement. This is at their discretion and isn’t guaranteed.
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