The Battery Module Search Continues: EIG

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Maybe I should say, “Ends”.  This is pretty much everything.

These are the EIG prismatic cells, here’s a spec sheet on the 20ah version.  They’re awesome.  Not quite as high as RC lipo in the discharge rate, but rock solid, safe, and long-lasting.  And they come in modules.

Here’s the link to the module page.

And here, is one of my, well, friends.  Who’s been working with them.  And building a bike with them.  AND HASN’T TOLD ME.  Kyle, I’ve got BATTERY MODULES and YOU DON’T Ginaven.

Here’s his R6 with the modules laid out, except in a non-hot-swappable way.

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…definitely promising.  Also, fairly expensive.

I keep going around in circles.  Here’s a factory-built good quality battery module with an integrated BMS in a workable form-factor for mounting four to six on a medium-sized motorcycle.  However, they’re expensive, and the chemistry isn’t up to the 20-30C range I would like.  And the chemistry isn’t really interchangeable.  So it brings me back to the enclosure.  Get a good enclosure system together with connectors and hardware for locking the modules in, and make it cell-agnostic.  Then you can use the boxes to run any cell chemistry you can fit into them.

So yeah.  The Quest continues…

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11 responses to “The Battery Module Search Continues: EIG

  1. In my opinion, currently the best bang for buck is a combination of CALB “grey” CA-series cells and bottom balancing with no BMS. You can get the CA cells in 40 Ah if you need small. They can easily give you 10C (400A with 40Ah cell). I currently use the old blue CALBs which can do about 7.5C. BMS, especially in motorcycles, is completely unnecessary. Avoiding BMS will let your cells give all they got and bottom balancing will protect them very well. See my post http://dy.fi/r0k

    • “Maximum Discharge: 2C”. hmmm. Where are you getting 10C?

      Even at 10C that’s pretty lamesauce compared to RC lipo. Has RC lipo spoiled me for all time? lol

      • Never trust the Chinese specifications. They will paint whatever picture they think the buyer would like to see. Not to mention that everyone has their own version. Case in point is the self discharge, which the cells do not have at all. The just gave the “less than 3%” because people wouldn’t believe they have none. With BMS they will drain surely.

        Here’s Jack charging a CA40FI cell at 120A (3C):

        And here he’s discharging at 480 A (so make it 12C):

        The cells will handle that just fine with no sweat and no swelling either. Don’t let anyone tell you otherwise (unless they have proven it by testing – typing is not testing).

    • Uh, yeah. According to my weak maths skills, you’re looking at fairly huge density differences. The EIG give you roughly 3x the wh/volume, and about 2x the wh/weight. CALB? Pretty much a FAIL in my book… but thanks for playing. (You did say “bang for the buck”, though, and there’s nothing out there that beats the RC lipo hardcase packs for that. So, yeah, no.)

      Always great to see Jack waddling around the set, too. Too bad I can never stay awake long enough to actually hear what he seems to be trying to say. (As far as manufacturer specs vs. Jack, I’d say it’s a toss-up in the credibility department.)

      I’ll just keep trying to type myself smart… lol! (Sorry, I have to ask. Have you actually run the tests yourself, or are you just typing Jack’s results?)

      • I use blue CALBs, have pushed them to the max, bottom balanced, drained whole pack to 2 volts per cell with no damage and so on. I don’t have first hand knowledge of the grey cells, but I tend to trust “live” video more that type-to-smart on forums with no data or video. Or printed specifications from China, for that matter.

        You can use the youtube’s 1.5x or 2x speed feature to speed Jack up if it’s a problem. 🙂 The thing about Jack is that he tests the cells, on video, admits if he’s wrong, even showed how he burned a table by leaving some broken A123 cells on it and so on. I really don’t subscribe to his views on other things at all and I probably couldn’t work with him though.

        LiNiCoMnO2 cells have higher energy density for sure. However, from what I’ve gathered it’s not quite as stable as LiFePO4. If you’re happy with LiPo then I suppose you won’t have a problem with those either. I have to say the look quite amazing… on paper.

      • Fair enough, thanks for the clarification. Personal experience trumps all the testing in the book, but then there’s the objectivity problem… I’m starting to see a pattern. The battery choice is clearly one of the most expensive, complex and fast evolving technology decisions in the entire build process. Once people settle on a particular battery system, they tend to feel they’ve found the Grail and all other options are somehow inferior. There’s a lot of chest beating “typed” on the interwebs.

        I’ve long thought we’d be well-served by the combination of real industry rating standards for batteries, and some exhaustive testing by reputable independent facilities. Obviously a lot of testing has been done, but the OEMs who do it won’t publish the results. Ford ain’t gonna spill the beans to Toyota as to which cells they found to be best. Until we see that, we’re left with Jack and the like.

        Having done a few decades worth of testing on digital photography equipment, often designing my own tests (for publication as well as for the general photography community) I can say that most tests simply beg more tests. After even the most sophisticated tests, you always wake up in the wee hours thinking “Why didn’t I do this or that?” Every time I made test results public I got questions like, “OK, but how about running the tests with these parameters?” It’s never ending… and far from conclusive.

        …and mostly because the question “Which is best?” Is a dumb question. The question should be, “Which is best for what application?” (And yeah, for what I’m doing? I lub my RC lipo!)

    • “The battery choice is clearly one of the most expensive, complex and fast evolving technology decisions in the entire build process. Once people settle on a particular battery system, they tend to feel they’ve found the Grail and all other options are somehow inferior.”

      That is true. Human beings always want to tell themselves that the decision they’ve made is the best one and quite many wish to tell others about it too. I don’t pretend to be immune to this. I try, but I may fail. At least I’m not actually trying to sell anything.

      This problem is greatly emphasized in the BMS stuff. They cost a lot and they are also something you can pretend to easily know something about or even build your own. Perhaps even think you could make a buck or two in doing so. It’s easy enough to tell people your house will burn if you don’t protect these dangerous batteries with a magic BMS.

      • Yeah, that’s true, and the more someone invests, the more they need to feel they’ve invested wisely. Owners of expensive cars are the worst. I love telling them that my $1200 Neon gets 35mpg.

        Of course, my decision to buy RC lipo was different. It was the BEST DECISION EVER!

        😉

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