Which batteries to use?
 

This year we are allowed to use one of six different batteries per R31?. Does anyone have an advice on which to use and which not to use? Any experiences with any of these batteries?

R31:
"The only legal source of electrical energy for the ROBOT during the competition, the ROBOT battery, is one of the following approved 12VDC non-spillable lead acid batteries:

Enersys (P/N: NP18-12)
MK Battery (P/N: ES17-12)
Battery Mart (P/N: SLA-12V18)
Sigma (P/N: SP12-18)
Universal Battery (P/N: UB12180)
Power Patrol (P/N: SLA1116)"

Thank you,
Brycen Wershing
1678- Citrus Circuits

Re: Which batteries to use?
 

All of the listed batteries are essentially identical (in form, function, and specification). FIRST does that on purpose, for both safety and team parity. You probably got an Enersys battery in your Kit of Parts (two, if you're a rookie team). You can buy any of the listed batteries as spares, and they will be interchangeable.

Re: Which batteries to use?
 

Here's a thought: Buy one or 2 of each, test them*, and report back to us. We'd like to know too...

*If you need help designing those tests, just ask.

Re: Which batteries to use?
 

The batteries from Andymark are good, aside from the fact that they are 17.2Ah. Our team uses the same MK ES17-12, but with 18-20Ah. This is only because they last longer.

Re: Which batteries to use?
 

Some of the specs are noticeably different. That may be real or it may just be differences in the way the two manufacturers test or rate them.

Re: Which batteries to use?
 

These different types are available from different sources if you were to order an NP18-12. These are the functional equivalent batteries to the NP18-12 to make it easier for teams to obtain additional batteries locally.

Re: Which batteries to use?
 

I think this is a welcome change that allows you to obtain your batteries locally in many cases.

If you walk into a local battery seller, and ask for a MK Battery ES17-12, they will probably look it up and come back with some other brand anyway. Any differences between these are so slight as to be imperceptible, although I'm sure there will be many discussions on here with anecdotal evidence that certain brands are better or worse than others.

Universal Battery and Power Patrol are widely available brands. Battery Mart, I believe, is a house brand for a wholesale outlet.

Andy Mark is already out of batteries for the season, so this will help many teams. Shipping on these batteries is expensive, too, so anything that helps teams obtain them locally is of help.

I'm surprised they missed several other manufacturers that make equivalent batteries.

Re: Which batteries to use?
 

Where are you seeing this?

This shows otherwise.

Re: Which batteries to use?
 

I don't think they did miss them. From the R31 blue box: "To seek approval for an equivalent battery, please contact frcparts[at]usfirst.org with the battery supplier and part number. Approved batteries will be added to the list above." (Slight change so the contact doesn't get spammed to death.)

Re: Which batteries to use?
 

But fortunately they've provided a system to suggest additions by emailing frcparts@usfirst.org

Edit: Whoops, Eric beat me to it.

Re: Which batteries to use?
 

Only the FirstChoice is sold out. As Ankit said (with a link), you can still buy the batteries from AndyMark.