What Battery Config do you use?

I am curious where the battery connector ecosystem currently is and where it is going. I read the battery upgrade paper and was thinking about if it was right for us.

What Battery Config do you use?
  • 6 AWG Wire with SB 50 Connectors
  • 4 AWG Wire with SB 50 Connectors
  • 6 AWG Wire with SB 120 Connectors
  • 4 AWG Wire with SB 120 Connectors

0 voters

IF you did anything other than the first option did see any quantifiable performance gains. I know the math behind the resistance, what I am curious is if you saw any real world physical difference in your robot performance.

IF you went with SB 120 connectors did you have problems where you wanted to share (loan or borrow) a battery from another team and couldn’t because of the differences.

Also did you make a 120 to 50 adapter? Did that negate any gains from the upgrade?

No love for 2awg?

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Do you use 2?

Yep. On the battery side, as of some recent upgrades for this past season.

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Can you actually tell the difference? That is what I am really fishing for with this poll and associated questions. changing to 4 or 2 awg would be more weight and an added expense but can anyone notice a real physical performance change in their bot with the upgrades. I also assume you are using sb120 with 2, not sure how you could jam it into a 50 and if you did wouldn’t that negate a lot of the gain.

We did. Before we switched to the larger gauge, our battery connectors would be warm after a match. With the larger gauge, they stay cool.

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Upon switching from 6 to 4awg we documented an improvement in battery performance that enables our robot mechanisms to draw ~4% higher total current prior to brownout.

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This is good to know. Did you stick with sb50? and did you change the PD(P/H) side?

One of our changes was to switch to a different color of SB50 connectors that has a higher strength to them. We found the default SB50s came disconnected too easily for our liking. (I think a game piece hit the battery side cable just right and pulled it out at one point.)

The down side is the connecter, while still SB50, isn’t compatible with most of the connectors from other teams.

1293 did a big overhaul of its battery fleet between Electric City and Championship, but we stuck with 6/SB50 because we had other places to allocate those resources.

I’m open to gauging up the wire, but I think we’ll stick with SB50s. Couple reasons:

  1. We’re cheapskates.
  2. We borrowed four batteries from local teams to supplement our stash for Championship. All were marked as pretty fresh batteries. All tested worse on a CBA run than our 2020 batteries (which, granted, arbitrarily low runtime but still cared for). I’ve got a workshop kicking around in my head as a result, but suffice to say I think loaning batteries to partners is a concern.
  3. Between the Battery Beak, our scouting inverter, our 10ish charger banks, etc etc etc it’s just a little bigger job than you think it is at first blush.

Note that you can do this for chargers or something like your Battery Beak, but 2022’s R609 says “a single pair of Anderson Power Products…SB type connectors”. Some flavor of that rule has been in the manual for many years, so you will need to pick a horse and ride it.

Switching to another color of SB50 housing did nothing for you except make your stuff incompatible with other teams still using the red/pink keying. But if you ordered new high detent contacts with them, that would’ve helped.

In all cases, someone who doesn’t secure their battery connectors together plays with fire.

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Yes, SB120s.

It’s definitely a marginal gain but we’d been using 4awg wire with SB50s for some time.

The leap to SB120s this past season was brought on for a bunch of reasons. We had slowly been procuring all of the parts for the upgrade and the pandemic meant we needed a full set of new batteries regardless.

I’m still not 100% happy with it and I think we need to look at some higher strand count 2awg wire for the next set that we do but, overall, I think the upgrade was worth it given the timing.

That being said - if you’re looking to save on cash then the key importance here isn’t the size of the wire or the connector… it’s the time you spend on the crimping, heat shrinking, and fasteners.

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The who what where?

Anderson offers several colors in their SB50/120/etc series, but these are all for keying for various voltages (or whatever you want) and afaik offered no change to the actual contacts and retention.

There might be third party connectors with tweaked geometry to do that? But that’s a whole can of problematic worms.

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Echoing this, any marginal gain from 4 awg is marginal compared to having developed a design and process and good tooling/fasteners.

On the robot side, bolting down the sb50 also ranks above gauge size in importance.

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Ye, but I believe those are still all in the same housings? (sans the Powerclaw PCB contacts) Been a few months since heavy datasheet sleuthing.

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Definitely. Our inability to borrow batteries from our alliance members led to brownout issues during our later rounds in Einstein but we were also rotating between two MK batteries (the rest were Interstate ones that we realized weren’t as good). If we had SB 120s on more MK batteries (which we’re now doing during offseason) then it wouldn’t have been a problem for us but using SB 120s did prevent us from borrowing when we needed to.

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95 has been running SB120s for a few years. I don’t think it’s ever come up, but if it did it wouldn’t be a big deal.

We always bring a few generically sized 6 gauge/SB50 assemblies, so if we needed to borrow a battery we could swap the robot side connector and deal with the performance drop. We could also swap a sb50 onto one of our batteries if we needed to loan one out. The potential hassle of that swap is, in our opinion, worth the extra bit of margin above brownout the larger wire gets us.

Something else to consider is that we always keep our large gauge wire as short as possible and those assemblies are very specific to the robot. Even when we ran sb50s I’m not sure that we’d always have been able to loan a battery to another team and be sure it would physically fit.

I guess my point is if you plan on loaning or borrowing batteries it makes sense to have spare sb50 cable assemblies on hand regardless of what connectors are in use.

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