I am an electrical engineer but Apple does not sell batteries directly to the consumer. Instead, they ship it to the authorized service centre. The service centre charges a lot for a new battery(around $200 or more). While going through Amazon, I was able to find iPhone 6 batteries for $30-50. My battery is ok for now but I was wondering if it is safe to put a 3rd party battery
https://www.amazon.com/Replacement-Battery-iPhone-ScandiTech-Repair/dp/B01B4TEJUM/ref=sr_1_1?s=wireless&ie=UTF8&qid=1483451890&sr=1-1-spons&keywords=iphone+6+battery&psc=1&smid=A3PXDB0WEUA1G8
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Is it safe to install 3rd party iPhone 6 batteries?