As the wiring lead of Team 811, I recently had to recycle a total of 10 batteries… (8 in which were all killed by our 2018 bot). Right now we have 4 operational batteries: 2 Enersys batteries, a Duracell battery, and the MK Battery from the KOP. I wanted to pick up another couple Enersys batteries but I couldn’t find them anywhere! Outside of Enersys, what batteries have personally done everyone well? Our team has had the best experience with Enerys, Duracell, and Werker batteries, though it seems that Interstate batteries and Power Sonic are getting all the hype nowadays. Any recommendations?
If you do end up choosing MK, call them up and tell them that you are part of an FRC team. They will get you an FRC battery and may give you a discount/free shipping.
MK or Duracell have been most reliable for us. Another crucial factor is proper cycling and charging with a quality charger.
We have some batteries that are still in great condition after three or four years.
Another crucial factor is to NEVER let the batteries sit partially charged. Recharge them right away after use, and occasionally during the summer and off season.
And by “right away”, I hope you mean “after 20-30 minutes of cool down time following a run with the robot”. But yeah, I wouldn’t want them to spend days and days discharged.
So we have yet to run this year’s battery data but we have found that Duracell batteries normally preform the best. However we have had I think one “die” on us, not in competition just they started acting weird so we diagnosed them. we believe that it has a bad cell so we set it aside for further testing. However they were also the batteries that received the most wear and tear so to speak because they were the ones that we always used. We have our 2018 battery data published here. For 2019 all of our 4 Duracell batteries were within the top 10. Specifically 1, 2, 4, and 5. If you have any questions please ask me and I would be more than happy to answer them.
Agreeing with above that the key thing is to not let your batteries spend any more time discharged than necessary. The only really bad batteries I’ve encountered* were last year’s KoP batteries. The rule I’ve tried to follow is that as soon as the battery is no warmer than your [healthy] pitmate’s forehead†, charge it. If you don’t leave the batteries on float charge in the off season (and there are good reasons not to especially in unoccupied spaces), top them off at least once and preferably twice per month.
* That is, they did not perform well for at least three years when properly maintained.
† I don’t really know if this is the right temperature, but it’s worked for me so far and it’s reasonably consistent.
Thank you for everyone’s responses! We’ve concluded that we’ll buy one Duracell and one MK Powered battery and see which one turns out better. I also took a quick survey at a Week 1 competition and most teams seem to use Duracell and MK as well.
