But Apple ended the wait for the customers sooner than promised, The Verge reported on Saturday.
"We expected to need more time to be ready, but we are happy to offer our customers the lower pricing right away. Initial supplies of some replacement batteries may be limited," CNN quoted an Apple spokesperson as saying.
The slowing down issue affects older models, including iPhone 6, iPhone 6s, iPhone SE and iPhone 7.
Apple earlier admitted that it was slowing down older iPhone models to compensate for ageing batteries.
"We know that some of you feel Apple has let you down. We apologise," Apple said in a statement on Thursday.
"There's been a lot of misunderstanding about this issue, so we would like to clarify and let you know about some changes we're making," the iPhone maker said.
Besides the battery replacement offer, Apple said that in early 2018, it will issue an iOS software update with new features that give users more visibility into the health of their iPhone's battery, so they can see for themselves if its condition is affecting performance.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)