Larry,
The fully charged voltage of a battery, while important, does not mean as much to us as a batteries ability to hold a given voltage under load. If your batteries were stored fully charged. for any period of time during the time that you had them, they were more than likely ruined at that point. I have not lost a single lipo in more than a year and a half. A few of my $32 4 cell 3800's have more than 64 cycles on them and they are still strong. I now charge the same day I plan to fly and I discharge any unused batteries the same day. I am convinced that a good top end charger is worth every penny!!!! Most of you that know me, know that I have experimented with lots of budget stuff, Some of which has worked out well and some which hasn't. Budget chargers just DON'T CUT IT!!!! A charger without a discharge and Storage mode just isn't worth it even if free!!! You will pay for it in ruined batteries many times over!!!! I wrote the following in another post recently but its worth repeating.
There is ton of info on RCGroups.com on lipo battery care Read up on the research by a guy called EVERYDAYFLYER he is all over RCGroups and is considered the top expert on lipos.To give you a summery of his work and what has been working for me. Lipos should never ever be stored fully charged even 1 day can hurt them. Most chargers have a storage mode that takes the batteries to the proper level.. 50-60% is considered fine. If the lipo isn't going to be used for a few weeks or you cant fly in the winter then it good to put it in the refrigerator. I put mine in a doubled freezer bag squeezing as much air out as possible. NEVER FREEZE THEM!!!. Some people will argue that its OK to store them in the fridge fully charged for a few days. I kind of disagree with that as they still need a 24 hour warm up period before you use them. If they are in storage mode and in the fridge they also need 24 hour warm up period before you charge them. I have been using this program since last year and haven't lost one battery yet. I have budget batteries with over 50 cycles on them and they still are as strong as new. Of course your milage may vary. All the batteries that I did not have on this program have failed.
On another note, I know that the next thing that will be asked is."How come it takes so long for my charger to discharge the batteries?". Well most budget chargers do not have a very high discharge rate. I did the whole budget charger thing so I know. I highly recommend a good charger like the I-charger 306B or the powerlab 6 or 8. YES they are expensive!! but you will make it up in saved batteries many times over. If you want to use a lower priced charger then get yourself a charger that is a minimum of 200 watts output. Most of those have a decent discharge rate even if a bit slow.
Topic: Battery storage (Read 703 times)
