Scavenging one nearly new battery to make another?

Batteries, Chargers, and Battery Management Systems.
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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 17 2019 10:12pm

Good to know...
So what are better/cheaper LiFePo cells? I'm the suspicious kind and when I look at the countless Chinese sellers of these thing and do a search on Aliexpress for say Samsung 18650 cells, I see lots of ads that say something like "...Turmera For samsung 3500mAh" or "...Kedanone For samsung 3500mAh 13A discharge"
WTF? "...for Samsung" Does that mean I'm buying Samsung knockoff by a company called "Tumera" or "Kedanone" ?
But that's the suspicious part of me raising its ugly head.
I don't think I've ever been cheated by a Chinese company, but I do think they don't have a problem letting language in the way.

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Re: Scavenging one nearly new battery to make another?

Post by Hillhater » Mar 17 2019 10:46pm

Why LiFePo cells ?
You need to settle on what you wantto prioritise..
72v or 60v ?
3kW ability, or something less. ?
Lighest weight ?
Low cost ?
Size/location restrictions ?
Long life cycle ?
Its always going to be a compromise but, When you have prioritised those, then you can start to figure out which cells and suppliers to use.
Use only proven , recommended , suppliers . Read more of this forum to find those .
Deal with the Chinese suppliers at your risk....Some ore OK , some are not.
You may get what you ordered, or you may not. And returns/complaints are near impossible
Sometimes you get nothing
This forum owes its existence to Justin of ebikes.ca

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 17 2019 11:10pm

Would love to build a moderate range, 72-volt system to take advantage of the Cyclone's 3k of available power. That said, according to the Cycle Analyst almost all of our dune riding is done at 10-15mph pulling less than 500 watts from that Gianormous 48v -20ah LiFePo4 battery pack that sits on the rear rack. We rode for 8 miles and used maybe a quarter of it's capacity? As stated earlier the battery tips the scales at 24 pounds and makes the kind of riding we're doing trickier than it needs to be. All that rear weight makes the rear end fishtail even when riding slowly transversing the dunes. But 72 volts would be nice hammering up a sand covered hill. The bike has a Nexus 3-speed IGH and in 'low' can climb pretty good already but 72 volts would make it even better. So I'm definitely gonna build something for the triangle above the Cyclone. I have moderate fabrication skills (I custom fabbed the hard mounts for Cyclone) and it's easy enough to relocate the bluetooth programmable controller so the space available is actually quite big. I plan on building some kind of sliding/quick detach mount so I can take the pack off and charge remotely from the bike.
So priorities?
1) Cost
2) Safety
3) Weight
3) Range

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dogman dan   100 GW

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Re: Scavenging one nearly new battery to make another?

Post by dogman dan » Mar 18 2019 6:26am

I'm gonna keep repeating, in 72v configuration, that 3000w motor can easily kill 80 18650 cells, unless you actually limit the amps to more like 1000w.

In fact, 4 cells in parallel is a bit small for 1000w. Oh sure, its within cell spec. But at the top of spec, those cells get all hot and bothered each discharge, blow a ton of their capacity into heat, shorten cell lifespan dramatically, etc etc.

To get a decent result, you need to start thinking in terms of 6p, or even 8 p. And even then, no 3000w spikes when you start up one of those sand hills. No way 160 cells fits in that triangle. So stop dreaming of that. But you can run 80 cells in the triangle, and carry another 80 on the rack. The one thing the 18650's have going for them is they are light, and pack into a triangular shape real nice. That's 18650 cells, like the Panasonics or whatever.

And one more time, lipo is the cell type that can pull 3000w, easily. 20s 10 ah of lipo is 8 packs of the 5ah 5 cell type packs. Get the 30c or better type for best results, but the cheaper 20c can do good enough. Spec on them is not realistic, but if you keep them under 5c they do fine. 10 ah of 72v at 5c, is 3600w. For a 30c pack, thats running one 6th of spec, keeping cool and less than 2 v of sag under full load. Again, you'd run 4 packs in the triangle, about 8 pounds or less, and then the other 4 on your rack, meaning about 12 pounds less on the rack than you have now. You can also mount 4 packs on the handlebars pretty easy too.

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Re: Scavenging one nearly new battery to make another?

Post by krlenjuska » Mar 18 2019 6:39am

dogman dan wrote:
Mar 18 2019 6:26am
I'm gonna keep repeating, in 72v configuration, that 3000w motor can easily kill 80 18650 cells, unless you actually limit the amps to more like 1000w.
3000w motor with 72v voltage will use about 40-45 amps. 80 cells is more than enough to give that current. Or i missed something?

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 18 2019 10:40am

I'm soooooo confused now....
80 cells in the triangle, and another 80 out back? WTF? I don't want anything 'out back' anymore. I don't want anything on the handlebars. I don't want anything anywhere but inside the triangle.
I'D LIKE 72 VOLTS (or 84-whatever) but am unwilling to pay $1,000 for a 160 18650 LiFePo's to make that happen. And I'm certainly not going to put that weight anywhere.
I could live with 52 volts, or even 48 but is the technology that 'sketchy' that even you guys (who know about 1,000 times more than I do on this topic) can't agree on it?
Again I say WTF?
And somebody please point me in the direction of a (non Luna) reputable supplier of 18650 cells at a reasonable price!

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 18 2019 10:45am

So what are better/cheaper LiFePo cells? I'm the suspicious kind and when I look at the countless Chinese sellers of these thing and do a search on Aliexpress for say Samsung 18650 cells, I see lots of ads that say something like "...Turmera For samsung 3500mAh" or "...Kedanone For samsung 3500mAh 13A discharge"
WTF? "...for Samsung" Does that mean I'm buying Samsung knockoff by a company called "Tumera" or "Kedanone" ?
And are these batteries on Aliexpress the 'good stuff' manufactured under license by Tumera, or Kedanone, or whomever?

krlenjuska   10 W

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Re: Scavenging one nearly new battery to make another?

Post by krlenjuska » Mar 18 2019 10:58am

mammonista wrote:
Mar 18 2019 10:40am
I'm soooooo confused now....
80 cells in the triangle, and another 80 out back? WTF? I don't want anything 'out back' anymore. I don't want anything on the handlebars. I don't want anything anywhere but inside the triangle.
I'D LIKE 72 VOLTS (or 84-whatever) but am unwilling to pay $1,000 for a 160 18650 LiFePo's to make that happen. And I'm certainly not going to put that weight anywhere.
I could live with 52 volts, or even 48 but is the technology that 'sketchy' that even you guys (who know about 1,000 times more than I do on this topic) can't agree on it?
Again I say WTF?
And somebody please point me in the direction of a (non Luna) reputable supplier of 18650 cells at a reasonable price!
You can make 20s4p battery pack with cells capable of 10+ amps continous and your pack will probably run without issues.
I think main problem will be small battery because you will be able to run your motor for 15-20 minutes with this pack.

If you can - make bigger battery.

About voltage - your motor is 72 volts or what?

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 18 2019 11:11am

as I understand it... (or thought I understood it anyway) my Cyclone 3k mid-drive motor is rated to take 72 volts and provide 3,000 watts of power at that voltage. I've been running it on a 48 volt system (battery pack and bluetooth controller) and the Cycle Analyst says it's drawing/producing 2,000 watts of power at that system.

krlenjuska   10 W

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Re: Scavenging one nearly new battery to make another?

Post by krlenjuska » Mar 18 2019 11:18am

mammonista wrote:
Mar 18 2019 11:11am
as I understand it... (or thought I understood it anyway) my Cyclone 3k mid-drive motor is rated to take 72 volts and provide 3,000 watts of power at that voltage. I've been running it on a 48 volt system (battery pack and bluetooth controller) and the Cycle Analyst says it's drawing/producing 2,000 watts of power at that system.
If 48v speed is enough for you - go for it. This way you can make bigger battery.

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 18 2019 11:44am

and when you say "be able to run 15-20 minutes with this pack" I'm assuming you're talking about 15-20 minutes at full throttle/ 3,000 watts 'draw' ? Because I can't imagine doing more than 10 or 15 second bursts of needing that kind of power. Most of our riding is pulling 500 watts or less through the system.
Or am I missing something here?

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Re: Scavenging one nearly new battery to make another?

Post by krlenjuska » Mar 18 2019 12:00pm

mammonista wrote:
Mar 18 2019 11:44am
and when you say "be able to run 15-20 minutes with this pack" I'm assuming you're talking about 15-20 minutes at full throttle/ 3,000 watts 'draw' ? Because I can't imagine doing more than 10 or 15 second bursts of needing that kind of power. Most of our riding is pulling 500 watts or less through the system.
Or am I missing something here?
Yeah at full throttle. I guess your motor will use 10-20 amps in normal use. Maybe less.
But - bigger battery is always better choice because you will load less current from each cell and your ride can last longer.
Btw you dont have to spend 1000€ for your cells. You can buy decent cells at https://eu.nkon.nl/.

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 19 2019 9:43am

Sorry, I went to the website you suggested and didn't see any deals there. And I'm getting just a little confused on what's the best 'chemistry' out there for Lithium Ion 18650's...so I guess I'll stick with LiFoPo's. So the search continues for a reputable supplier with the best price. At this point it's prolly gonna be a Chinese supplier as I've had good luck with 99% of those I've dealt with in the past.

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Re: Scavenging one nearly new battery to make another?

Post by 999zip999 » Mar 19 2019 2:08pm

There are many favors of 18650 some 1amp cells some 30a cells. At 30amps it won't have much capacity. Because 18650 is the size or capacity of energy that can fit in the cell. How many amps is your controller rated for.

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Re: Scavenging one nearly new battery to make another?

Post by john61ct » Mar 19 2019 2:46pm


mammonista wrote: what's the best 'chemistry' out there for Lithium Ion 18650's...
There is no one best. Nor even one measure of good.

Seems most here value peak discharge C rate, but can't rely on mfg claims.

Energy density - Wh per kg - is objective, and LFP is weak on that.

Longevity is LFP's strong suite, but needs a quality maker, trusted supplier and depends greatly on user care.

Temperature issues, performance in heat or extreme cold

Safety, susceptibility to "thermal runaway"

Then there's price. . .



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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 19 2019 2:56pm

I believe I have the Yuyanking controller sold by Cyclone (at least that's the one they suggested). Blue tooth programmable and rated for 36-72 volts and 60watts maximum?

mark5   100 kW

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Re: Scavenging one nearly new battery to make another?

Post by mark5 » Mar 19 2019 2:58pm

About 18650 cell types:

Amazing new 18650 cells for E-bike batteries in 2015 by spinningmagnets
https://www.electricbike.com/18650-cells-for-e-bike/

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Re: Scavenging one nearly new battery to make another?

Post by 999zip999 » Mar 19 2019 3:07pm


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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 20 2019 12:36am

So my priorities again:
1) Cost
2) Safety
3) Weight
3) Range
Nearly all of them are interchangeable though. I have enough room in the triangle to build a custom box on a sliding mount with a relatively large number of 18650s. If I had to guess I can build something in the 100 cell size. That will require relocating the controller but no big deal.
The Cyclone motor is rated at 3,000 watts at 72 volts. The Yuyanking (sp?) controller is rated at 60 watts (I think). Most of our riding is mild off road (sand dune, sandy forest trails, beach) where we're not full throttle 95% of the time. The bike has a 3-speed IGH and my current 48 volt battery pack has enough punch for just about everything but the steepest hills. Still most of our riding is pulling 300-400 watts traversing soft sand hills at 10mph (or less).
Everyone says inexpensive 18650s are out there, but where? And what is inexpensive? I've been happy with my LiFePo4 -20AH battery pack but it's far too heavy to carry on the back rack for the kind of riding we're doing. So I want to move everything to the triangle. What's the best maker of LiFePo4 batteries and what's a reliable source.
PLEASE?

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Re: Scavenging one nearly new battery to make another?

Post by john61ct » Mar 20 2019 12:42am

A123 ANR26650 2500mAh, new $8-10 delivered

Best source for A quality is direct from maker authorized

http://a123batteries.com/anr26650-lithi ... 26650m1-b/
..
https://eu.nkon.nl/rechargeable/26650/a ... grade.html
..
http://queenbattery.com.cn/our-products ... l-70a.html




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Re: Scavenging one nearly new battery to make another?

Post by Hillhater » Mar 20 2019 1:34am

I Ask again,... Why LiFepo ?
Using those will instantly double the weight , size, and cost of any capacity pack you build ?
Sure they will last longer than Lico ,.... but you could build 2 packs of lico for the price of one LiFePo.

Another proven reliable source for cells ..and some premade packs..
https://endless-sphere.com/forums/viewt ... 31&t=61608
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dogman dan   100 GW

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Re: Scavenging one nearly new battery to make another?

Post by dogman dan » Mar 20 2019 6:08am

I'm sorry if Im confusing you. What Im trying to say is this. Big amps wont fit in your traingle, partly because you have a motor there already. The battery ends up being too big. Dont believe it when they say the cells can handle it. they can, sort of, but they hate it, get hot, and don;t last if you use them that way. Im saying because you want it, does not mean you gonna get it. It wont fit, period, and that is that. you can fit a pack there that will put out 20 amps no problem, 1000watts. But your system will occasionally whack it with triple that, and kill it. So if the triangle is where you want it, you gotta program it down, or cut some shunts inside, or somehow get to a 20 amps controler.

I get your desire to use a safe battery type. I should get it, my bike burned my house two years ago. What I actually learned, was dont trust any type battery. So now that no f ing battery is ever entering my house again, I feel fine using the dangerous, lipo cells. A 44v 12s 10 ah lipo pack will fit in your triangle, and pull 3000w easily. But even in lipo, 72v does not fit so great inside that triangle. So that is where carry a portion of it someplace else comes from. Less than 8 pounds will carry fine on the back. Right now it suck huge with 20 pounds back there, for sure.

for an 18650 pack that might fit your traingle, and put out a solid 20 amps, this will do. The vendor is top notch. https://em3ev.com/shop/em3ev-52v-14s5p- ... e-battery/ He has some great triangle batteries too, but they need that space your motor is using.

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 20 2019 9:55am

Dogman,
A few years ago I 'chopped' my VW van and made it into a DOKA (German for 'double cab' pick-up). 97% of the people who see it say "effing cool!" with the remaining 3% saying "if you wanted a DOKA so bad why didn't you just go out an buy one?"
If I had the time and resources I'd do it again! (In fact I might try to make a business out of doing the conversions?)
Image
When I bought a fat tire bike I knew almost immediately I wanted to put a motor on it. Have you ever driven a fatty without one? Ugh!
Then I decided on a mid-drive and I figured a Cyclone would give me by far the most bang for the buck. A lot of people said, "Why not just buy a bafang?" or "that's an awfully big motor for hanging below the bottom bracket!" My answer was to spend a lot of time building custom mounts to put the motor inside the triangle. I'D DO IT AGAIN! The motor makes a lot of sense there. That said, there's still a lot of room inside the triangle (once I relocate the controller) for a huge custom build battery!!!
I am not mounting anything on the rack!!!!!!! The rack is probably going away!!!!! Because of the kind of riding we're doing any weight on the back of the bike is BAD!!!!!! Ditto anywhere else on the bike. It's either going in the triangle or it ain't going!!!
I hope you understand.
That said, the link you provided is for pre-made packs only.
- I want to build a custom pack.
- I want to put it on a sliding mount inside the triangle so I can remove it for charging to a safe outdoor location away from any structures.
- I want the best deal I can get for quality cells (I don't mind sales 'mark-up' but only within reason.
- I want to be able to pull 3k watts for the Cyclone, and I guess I thought I needed 72 volts to do that? Now you tell me that's incorrect?
- I love 'Vanomo' (Van No Mo) my DIY DOKA!

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mammonista   10 W

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Re: Scavenging one nearly new battery to make another?

Post by mammonista » Mar 20 2019 10:43am

By the way Vanomo is almost ready for paint after spending the past few months of intense bodywork.
Image

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Re: Scavenging one nearly new battery to make another?

Post by john61ct » Mar 20 2019 11:35am

OK, solid evidence for your DIY mech eng cred.

I would say go ahead and start, physically prototype & test for volume & weight and see exactly how many cells (thus Ah) you can fit, fat ones vs 18650, in different pack shapes.

Then compare the energy density of fat LFP vs 18650 LFP vs (lower-lifespan, riskier, cheaper) other-LI chemistries, also taking cost (up-front vs over X years) into account.

Voltage of course is critical, same with maximum discharge amps, yes important but neither impacts the above that much, so you can get started on that physical R&D and continue researching the cell purchase choices in parallel.

If brand new LFP turns out to be too pricey for you, an acceptable compromise will arise if you relax a bit, and be patient, leave yourself open to alternatives.

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