After having a discussion with one of my customers about leaving his battery charger on all winter, a practice I am certainly not a huge fan of, I decided to do this article.


On December 11, 2012 I charged this used G-31 house battery using my bench top DC power supply. I charged the battery to 14.8V and 0.2A of "accepted current" which essentially means this battery was full.


I then charged the battery at an equalizing voltage of 15.5V for approx 30 minutes. This is a standard practice for me when winterizing flooded or AGM batteries that can be equalized (currently only Lifeline AGM's can be equalized.

It is critical before winter storage to charge your batteries at the maximum allowed absorption voltage until current declines to less that .5% to .3% of Ah capacity. For a 100Ah battery this means 0.5A to 0.3A..