I don’t need it I don’t need it I don’t need it
Wait what’s the diff between the two sets of A123… I looked it up and the datasheets are basically the same
Also what voltage do people usually run the A123’s at? Something like 13s right?
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12s LifePo4 for 10s liion equivalent, 14s lifepo4 for 12s liion equivalent.
Those blue IFR26650 cells are supposedly like 10A continuous 15 pulse.
As far as the difference between the A123 cells, the M1Bs are the newer cell, replacing the M1A cells, the M1Bs are a bit higher capacity, 2.5Ah, but with lower continuous discharge, however they’re both insane power cells.
M1A: 2.3Ah capacity, 70A continuous discharge, 120 pulse
M1B: 2.5Ah capacity, 50A continuous, but same 120 pulse rate.
I’d definitely think the M1Bs would be worth the extra for the capacity since you won’t have to worry about discharge rating in most apps, just range.
Edit: really more a response to ShutterShock sorry.
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15s don’t be scared
Lol we decided to go 12s due to space constraints
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all kinds of new stuff just now
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lolz good deal
yeah same i was all happy checking all the batteries they sell and on checkout bam no shipping to canada T.T imma go cry i’ll have to stay with shitty batteryhookup or not since they ripped me the fuck up (10 powertool batts 2 bad out of the box and 60 dead 18650 batteries)
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did you write them and they wouldnt refund or send you other cells?
i sent a message saying i was very disapointed but haven’t got a response yet and i can’t ask for a refund as it is sold as is so i got fucked pretty hard (20 good cells for about 200 CAD kinda hurts. I even had bought 20 other ones before i could finish testing them (i asked to be refunded since they didn’t had shipped them) plus the ones that were good came up at +2100 mAH each when they’re supposed to be 2000 mAH or less. I guess i’ll have to wait to build my 10s8p battery : /
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Apologies if you’re aware, but you know about gently bringing cells back up from zero volts right?
I’ve found VERY few cells ever I couldn’t revive.
I bought a bunch of those $5 9S ATX packs in the fireproof cases that they said we all toast, wish I had bought 1000 of them, I managed to revive them ALL by using my bench PSU, current limiting to 0.250A and pushing them past the max charge voltage, the BMS came back to life and would bounce current as soon as you hit like 39.5V, once it hit a nominal voltage the CC charge would engage and I’d reset the max voltage to normal cell pack max. No clue why it works this way and I’ve seen nobody else using this method, but all of them had fully functional BMS and all cells fine, one had bad BMS with bad cells.
Zero volt cells you need to current limit to a very low charge until they get up past 2V or so, using a CC/CV supply. First charge they may have heavy self discharge, and/or low ass cap, but cycle a few times fully and they’ll usually rebound a ton.
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i would do that but i don’t have a bench PSU. I did try on about 10 of the bad ones to slowly charge at 300mA but my charger just stop charging at around 1.5 volts and when removed/stop charging drop back to .5 volts or less (liitokala lii-500 ) I have an Imax b6 (more than certainely a copy but idc) maybe I could use it to charge them past 2 volts ?
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So, afaik none of the lithium cell chargers, really can handle totally dead cells. I have heard of some of the high end RC pack chargers that can do a “revive” charge.
You can buy a small CC/CV module on Amazon for like $10 though, and make a charger with it and a DC power brick really easy. I bought a couple of these recently and it’s really nice: https://www.amazon.com/gp/product/B081YQQVHC/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
Already has a barrel jack so you can find a laptop power brick at a thrift store to power it.
Set the max current and you’ve got a functional bench PSU.
Unfortunately(probably fortunate for almost anybody but us) all the chargers have too many safety features because of all the frankly excessive fear of exploding lithium cells.
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I’ll check into it. I also sent an email directly to bhu hopefully they’ll be able to help me out and not buying powertool batteries probably ever again to salvage at least.
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I get it man, it can be frustrating, but fwiw, it’s one of those things that just seems like you’re cursed until you reach a certain “critical mass” of information and tricks up your sleeve. Those packs I described, they sold with the expectation that many of the cells would be unusable, I’ve seen many videos of guys thinking the BMS’s were dead and pissed at cell caps being marginal, I thought the same until I learned otherwise.
I’d bet good money you can revive most of those cells. We’re so entrained by the idea of cell damage from lead acid, NMH, and other chemistries, and then the few aberrant cell chemistries that made big news, that we don’t generally realize how tolerant and safe most of them are. Even the “cycle life” charts most people dont understand. Standard NMC chemistries are almost always good for 1000 cycles at 100% DOD before they loose 20% capacity, but people go around talking about them being dead after 1000 cycles constantly. In a power tool pack, there’s usually 1 cell that has been worked 10x harder than the others, that’s when the batteries get recycled. The rest usually are 90% capacity still after a few cycles post revive.
Don’t give up hope, I can’t tell you the number of times I thought I got screwed on a surplus/salvage pack only to find out later I just didn’t quite “get it”. Good luck bro!
thanks ! yeah i get it gotta learn by making mistakes too I’ll get a bit more equipment and try to revive them plus it’s not like i had everything to make my esk8 (i only miss all the non electronic part of my build lol) But if you have any website in mind other than BHU and batterycleaninghouse I could buy batteries from let me know !
thanks for the help 
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TBH they’re the main resources, and we’re lucky to have them. Otherwise you have to wade through ebay. There’s lots of sellers there, but techdirect and other fucks are so hit and miss, shady with their info, etc. Trust me, BHU and BCH are awesome comparatively. There’s EVWest and Jehu’s reseller of the week, but they always come with a major kwh premium, or are trying to sell some other shit.
Most of the time, the moment some youtuber has schilled some shit, it’s 2 or 3 times as jacked up in price as it’s worth… For used cells, except in situations where they’re testing at near full capacity or are in a really special config or package, just always defer to the $100 per kwh rule as a baseline. With few exceptions, if they can’t guarantee near 100% capacity, or they’re not particularly special cells (like the large headways), it’s nothing special in terms of deal if it isn’t below $100 a kwh at nominal capacities, or even adjusted. BHU and BCH have been really pushing those margins. Now, anytime some cunt on YT posts a video with a stupid shit eating grin and a fatty physique that makes you feel really uncomfortable, even though they can’t possibly be looking at you personally; just know, there’s a catch, usually in price, in exchange for ease of implementation.
If you want to DM I can point you toward some ebay sellers to watch, and some exceptional values for most applications. That said, even though I’ve got tons of cells on hand, I just bought 48 molicel p42a’s for my mtb build (dirt cheap for new top tier power cells fyi).
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how much for the p42a cells you pay? those are new to me and seem the best power/energy dense cells available. wish they were bigger though…all this stringing together cells in a parallel is silly (unless your on a skateboard trying to be slim)
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