I have two sets of these 14ah tattu packs that fueled fairly intense skating during Covid in San Diego. I have metr records Somewhere, but I ran 4wd on lacroix 6389 motors, limited only by ESCs.
Not much of speed demon now, but I definitely put them through their paces.
These are kinda puffy now, okay for a little bit more.
The RC car guys are the worst. Don’t watch any of thier lipo brand reviews on YouTube. The Rc heli and X scale drones guys have better takes. They use and need all the power they can get to keep expensive flying things in the air.
It does seem like a good deal for that brand, and I guess maybe I shouldn’t cheap out if I go lipo, but that ends up close in price to doing 5p p42as, which, if I’m not considering money, is probably what I want. Maybe I should just bite the bullet and do that. The lipo is lighter by a fair bit, though, which is at least one positive for it.
What a crock…25C at 16Ah means they should be claiming a 400A rating.
But they rate it at 300A “peak” (whatever that means) and 120A continuous. Perhaps because the 10AWG leads literally melt in a few seconds at about 330A?
Then why call it 25C?
So much bs with LiPo…C ratings are utterly and completely useless and I am so confused at why so many worship at the temple of C.
That is far from the worst. Most of the lipos I’ve looked at don’t have anything other than a C rating and say you can pull 600 amps or more through 10 AWG and an XT90. From what I’ve seen, it actually seems next to impossible to get usable information about lipos.
Impossible to say. I’ve had them for 4 years, All the wild rides during Covid were on them. I was rigorous about charging to 4.15 for 99% of cycles. Never went low, always stored at 3.7 if not going to use that day.
During Covid, I’d say they got charged every day.
I guess my charging strategy doesn’t count as complete cycles if you are doing the math.
P4-p5 is on the bottom outside and p17-p18 you can see the folded nickel in this pic
Faaaaat braid too. Easily the best investment i made was a fat fat chisel for my haako, that shit sucks up the heat if you’re not laying it down fast enough.
What’s the consensus on Lacroix batteries these days ? Opened up my supersport for a maintenance check and it all looks pretty good. My put some insulation behind the balance wires and the nickel as at the moment there’s just shrink wrap.
Ive been taking apart a lot of Lacroix boards lately for battery repair and modifications. The best condition ones i see are like yours pictured - partly because i think they are done better and i think partly that they are newer/ fewer miles. If it’s not broken don’t fix it.
The only thing I would do would be to add some spots of silicone around the packs to lock them down better but only because i do that to all my packs. Only damage I’ve gotten to see on this style is some moisture or dirt got one of the adhesive pads loose and it bounces but only one of three ive seen and on the 7 cell enclosure type with the 20700 cells. The adhesive pads under those are usually amazing and a marvel with how good they stick - if you pry on them wrong you can pull the carbon fiber apart
The teflon (i think it’s teflon?) wire for the balance wires is super abrasion resistant and never seen any issues except at the connections- a bit of silicone here again.
Make sure the adhesive on the parallel/discharge connection bolts is good and replace any that is loose and make sure all the bolts are tight if you need to replace it but I wouldn’t touch it if the hot glue is still in good condition.
That’s exactly what happened to one of the cell groups . The shrink wrap had split and it was coming loose so I re-did it. The only other thing I noticed was the two negative wires coming off the battery are pretty thin but I’m sure they know / knew what they were doing .
This is why surface prep and cleaning are so important. Just grabbed some junk but good cells to make a quick 2s2p replacement pack for my friend’s bike light battery that died and the pos on one cell was dirty and welded all garbo. Was just from the junk pile so i make a second one with a little iso wipe and got much better results. Nickel is overkill but it was just scrap so idc
Assuming the lipo on the left will carry the main negative and the right will carry the main positive.
Is my balance wiring objectively wrong or immediately concerning? I have yet to warm up the heat shrink to ensure there’s still time to fix any mistakes.
(I can separate each balance wire so they’re not touching but I did a poor job of estimating wire lengths, they’re not bent at consistent angles but I don’t think any are bent at a sharp enough angle to cause problems)
Why is the red from the most neg pack balance connected to the adjacent balance lead? Or is it just taped off?
Seems correct if it is taped off (not connected) but pulling the pin out of the extension is a better way BUT it looks like the connection is covered in shrink so pita and works both ways 6 of these or half dozen of those
Just taped off, I had hoped it would better illustrate the wiring to have it more “readable”
I have a few extra of the balance connector I used, I’m going to try just pushing the pin out from the front without undoing the heat shrink and if that doesn’t work I had planned to just clip it shorter and heat shrink the individual wire with glue lined heat shrink.
Do not ever do pull tests on the negative terminal of batteries that you weld 0.3 copper onto (plus the 0.1 nickel plated steel) at the recommended 65% setting.
The weld is stronger than the housing of the battery cell, trying to remove it punctures the cell.
This was tested on a molicel P42A. Other cells may or may not behave the same way.
