We just got a quote for new batteries from MK as it has been a few years since we have replaced our fleet.
With Freight and Logistics added the price after shipping is $30 off buying from Andymark.
Currently looking at $61 a piece, almost double the cost from our last purchase. Andymark is priced at $63 each after shipping.
If anyone else is purchasing soon, wait until after 11/1 and the logistics charge apparently won’t apply. And then pick up your batteries if you can to save at least $100 on freight. Doing both of those will bring us back down to $45 each. It looks like the days of discounts and free shipping are gone, unless I’m just unlucky.
Shipping might be cheaper for teams located closer to REV’s offices (or local enough to DFW for pickup). The days of free shipping are likely long gone with how the state of everything is at this point.
We always pick up our MK batteries from a supplier that is nearby. Looks like there is a MK distributor in Grand Rapids. Might save you some shipping costs.
When we called in August mk told us to just them from andymark as they’d be the same price so we did that. Then REV started carrying them for $10 less for a pair. Don’t know what the shipping cost difference would have been but I do know andymark is closer to us
MK told us we can pick up at the warehouse in Lansing to save shipping. Brought it down to the $45/battery on the quote. We will probably go that route and try to time it with someone travelling across the state for a pickup.
People might not want to hear this, but I prefer to pay more than the minimum for shipping. I buy enough batteries so that the order must be shipped LTL by a freight company, rather than by a parcel service.
Doing this makes me feel more confident that the batteries have experienced lower peak accelerations… My reasoning being “If the batteries are strapped to a pallet, than they probably can’t be thrown by a person”
Here’s the damage we saw on the last order we had shipped via UPS, in 2017.
Shipping costs more than a pair of batteries themselves.
At least its not so bad like it would be for pool noodles. We always buy them from the mainland because you cant get the required FRC size here in Hawaii in recent years. This is similar to just about anything we buy.
Not sure if it makes you feel better or not, but your shipping is only $8-22 more than ours. Even though yours would cross a large part of an ocean and ours would travel just over 100 miles on a major interstate highway.
Teams that don’t play a ton of matches don’t run their batteries as hard. 1293, who has only played two in-season events a year twice in 19 years (2019 and 2022, the latter due to hell freezing over), has a 2016 battery that’s still testing astoundingly well on the CBA. Better than the 2019 KoP battery, even (though I recognize that’s a low bar to clear).
Teams that treat their batteries extra well will get longer lifespan out of them. (Not saying 95 doesn’t.)
Some teams are pickier about battery performance and prefer to throw money at the problem rather than let it bite them in the butt.
As my grandfather would’ve said, some teams don’t know good because they ain’t had good. (Not saying 3572 doesn’t.)
we keep our batteries on a ten bank Battery Tender unit that has been good to us over the years. We generally play 2 full district events with runs to the semi finals or finals regularly, then at least MSC annually. That and practice means that we definitely use them (~50 matches, plus some practice if we are low on practice batteries).
That said, we don’t build robots that are battery hungry. For practice matches at events we have run as hard as we could on the same battery for 4 matches in a row before needing to swap out. We might be a bit conservative on our allowance for current draw on mechanisms, but we also don’t spend $500 every year on batteries. We do have standards we follow and testing to support our standards and we’ve never failed to operate in a match due to a bad battery. We bring 14 batteries to each competition (10 match batteries and 4 practice) so each battery gets at worst 2 matches per competition played on it.
Answers are probably going to be subjective. I feel we treat our batteries better than average using this scenario:
18 batteries total in circulation.
12 batteries (newest ones typically) go to competition.
6 batteries (oldest) used for practice.
6 new batteries per year, 6 oldest ones go to battery heaven.
This means a competition battery sees 2 seasons before being relegated to powering practice robots and software programming.
12 station battery charger (Qty. 4, Noco 3 gang). Newest 12 batteries are plugged in continuously even over the summer months.
6 station battery charger (Qty. 2 AndyMark 3 gang circa 2014?). Oldest batteries are plugged in continuously.
Discharge wise, we aren’t nice to our batteries. Our robot are typically very hungry and a battery is lucky to make it 2-3 practice matches before experiencing brown outs. I would guess that practice/development time verses competition time is at least 4X (we practice more than we compete). The only saving grace for the battery is since there is 18 of them, the number of discharges per battery is spread out.
In conclusion, getting 2 years of use out of an 18Ah battery that gets discharged routinely in minutes, I think is pretty good. This is more likely an exercise in managing expectations since I would be upset if my car went through batteries that fast.
I’d guess 1 and 3 are most applicable, with maybe just a bit of 4. I think we treat our batteries pretty well, but for details you should ask @JamesCH95. We definitely weren’t nice to our 2019 batteries (left in the shop for 2 years), and the 2022 set was amazingly better. We also like throwing money and motors at problems, so we end up with power-hungry robots. (Hedy has 11 neos and 4 baby neos)
Not to say we intentionally abuse them, far from it. We format new batteries appropriately, desulfate them annually, and keep everything stored at a good SoC as best we can.
…pretty much…
In pushing gearing, mechanism design, and motor quantity/selection to minimize cycle times/maximize scoring speed we tend to obliterate batteries during matches. Taking a battery out of a robot after match at 9-10 unloaded voltage is not uncommon for us.
This depth of discharge over the course of 3-4 events/year and a good amount of practice simply wears them out in a season/year.
