Battery replacement
How do I go about replacing my battery to MacBook Pro late 2013
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The 2013 MBPro is "Vintage" and only an Apple Authorized Service Provider will be able to repair it (those that actually perform repairs in their own shop as opposed to mailing the laptop to Apple). Plus some laptops should now be eligible for an official Apple battery repair for up to 10 years, but it may not be for this 2013 model and it may not be guaranteed (Apple's documentation here is a bit confusing). IIRC, we were unable to get a Battery replacement for our organization's 2013 MBPro through an AASP, but you can certainly check with an AASP to be sure.
Obtaining service for your Apple product after an expired warranty - Apple Support
If an AASP is unable to perform the repair, then you can get a third party replacement battery from OWC:
https://eshop.macsales.com/shop/laptop-batteries/macbook-pro
Go for the official Apple battery if it is still available since the quality of third party Lithium-ion Batteries is extremely poor even when purchased from a respected vendor such as OWC. The battery is glued onto the underside of the palmrest & trackpad and is difficult to remove. You also must be extremely careful since it is very easy to puncture or damage the battery plus you must properly store the battery in a metal container (best to tape the battery connector) and give the old battery to an appropriate recycling center as the batteries contain toxic & dangerous materials that should not be put in the regular trash. OWC has video instructions showing the replacement procedure. Videos always make things look much easier than they actually are. Perhaps some AASPs will offer to install a third party replacement battery.
