Restoring/Recharging Over-discharged LiPo (Lithium Polymer) Batteries!

By Gabriel Staples
Written: 5 March 2014
Posted Here: 13 Oct. 2014
Last Updated: 7 Feb. 2015
-added Q&A section & link - 7 Feb. 2015

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Though I first posted this article on my Instructables page, I decided to update it and repost it on my main website here in order to keep my articles more consolidated and easily maintained by myself.  From this point on, I will keep the most up-to-date version of this article right here, instead of on my Instructables page, so if you want the latest info, read here.  Don't forget to subscribe to receive an email whenever I post something new by clicking the subscribe link at the top-right of this page!  I will never use your email addresses for spam.

A LiPo that self-discharged, while in my plane, hanging overnight in a tree. :(

Intro:

LiPo batteries should never be discharged below 3.0V/cell, or they may be permanently damaged.  Many chargers don't even allow you to charge a LiPo battery that is below 2.5V/cell.  So, if you accidentally run your plane/car too long, you don't have your low voltage cutoff set properly in the ESC (Electronic Speed Controller), or you leave the power switch on, forget to unplug the LiPo, get your plane stuck overnight in a tree (the same tree, three separate times, for foolishly flying in areas too small because you are too excited to fly and it's almost dark), etc. etc., you may find yourself in a situation where you've discharged your LiPo down well below 3.0V/cell.  What do you do?

Many people toss the LiPos in the trash.  I don't.  I restore them.  Here's how.