Cheap high rate 24V pack?

Chalo

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I'm building a bike for a friend of mine who is recovering from a major injury. The BLDC hub motor I'm using has a very fast wind, so I have sourced a 24V 25A controller to put it in the correct power and speed range for the application.

Here's my puzzle: I need to find a safe, turn-key, self-contained battery pack for the bike that can deliver a true 25A current continuously. Almost all the frame or rack mounted 24V packs I have found are rated for 10-15A, with a few rated for 20A. A pack that can give more than 25A would be a bonus, because then I'd be able to fit a higher current controller later if he wants one.

The pack doesn't need a huge amount of capacity, but it needs to carry whatever load this controller can put on it. I'm passing the hat among this guy's friends for the battery pack (while I'm donating the bike, motor, and labor to assemble). So low cost is an important criterion. I was hoping to find something workable for less than $400.

Also, this guy is not technologically inclined, so the battery needs to be plug and play, in a durable case, with full BMS and no significant risk of fire. I can't expect him to deal with parallel packs.

Ping packs appear to fit the power requirements, but two months lead time and a naked shrink wrapped pack aren't what I'm looking for. Ideally, I'd like to deal with a USA vendor.

Any ideas?
 
30 amps from that pack would be 1.5c discharge rate, so that is a plausible solution.
 
Can anyone recommend someone who is building packs out of quality cells in the US at a fair price?
 
Go to this website ru.nkon.nl and buy the 18650 with tabs already installed then go to Home Depot, buy home wall wiring, solid copper, 10AWG. Snip to length.

Also while you are at it, pick up some 18650 spacers
https://ru.nkon.nl/catalogsearch/result/?q=spacers

https://ru.nkon.nl/rechargeable/18650-size/price/0-5/brand/panasonic-sony-samsung-sanyo/min.-capacity-in-mah/2500-3500/discharge-current/7-20.html

Samsung INR18650-29E 2900mAh - 8.25A - 2.25 Euro
Panasonic NCR18650PF 2900mAh - 10A - 2.00 Euro

24V is either 6S or 7S depending on what your LVC is on that controller.
12Ah = 6S4P with them 2.9Ah cans and 24 cans total

1 EURO = $1.23USD
30 Cans (Need 24 but you'd have 6 spare cans) with tabs welding on by NKON
Price including shipping to Texas = 105 Euro's = $130USD

Comes down to, do you have time to build it?
And, do you require a quality BMS?

Hopefully someone here on ES has a quality BMS they could sell, keep that Plug & Play criteria you mentioned.

The thing going for this method, 100% known good quality pack, and its cheap.


Off the shelf
$650cdn delivered which is $500ish USD You know its solidly and quality built!
24V 23Ah from Justin - http://www.ebikes.ca/shop/electric-bicycle-parts/batteries.html

Justins LiGo packs are 36V
 
That battery from Justin has an impressive ah rating looks like a good deal.
 
Raisedeyebrows said:
That battery from Justin has an impressive ah rating looks like a good deal.

http://www.ebikes.ca/shop/electric-bicycle-parts/batteries/b2423lim-re.html

I agree, its 24V 23Ah and 50A(cont.) States Only 3 left - CAD$570.00 + CAD$80(Hazmat) = CAD$650 which is USD$512

You know the entire pack is 222% quality!

Thats why I mentioned the DIY in my previous post. I think with tabs already welded on, soldering is a breeze!
So low cost is an important criterion. I was hoping to find something workable for less than $400.
 
markz said:
Raisedeyebrows said:
That battery from Justin has an impressive ah rating looks like a good deal.

http://www.ebikes.ca/shop/electric-bicycle-parts/batteries/b2423lim-re.html

I agree, its 24V 23Ah and 50A(cont.) States Only 3 left - CAD$570.00 + CAD$80(Hazmat) = CAD$650 which is USD$512

You know the entire pack is 222% quality!

Thats why I mentioned the DIY in my previous post. I think with tabs already welded on, soldering is a breeze!
So low cost is an important criterion. I was hoping to find something workable for less than $400.


I am attempting to read any threads where the pre-soldered tabs were used building a pack, curious what the method of attaching strips to the tabs is, I'll keep searching.
 
ru.nkon.nl in the netherlands uses a tab welder. Key search term "Tab Welder" or "Tab Welding"

Soldering to tabs are easier and less heat damage because you are heating up the tab and not the metal on the can itself.

Its still a bit of work even with the tabs on there from nkon. But the work isnt all that much.
All I do is go to Home Depot and buy some 10/2 household wiring with solid conductor not stranded, it come with 2 conductors that are 10awg and a third bare wire that is 12awg, use 10awg for series, and 12awg for parallel. Strip the two 10awg and cut as needed.

24V is only 6S or 7S then if you use PF 18650 cans then they are 2.9Ah with 10A discharge. So say 15Ah is 5P, 45 cans in total. A decent soldering iron, some solder, wire strippers.

I'd say an average person with soldering knowledge could do it in, 2 or 3 hours.

It just saves a bunch of money that could go towards extra capacity in the battery, decent BMS which is what a plug & play would require for the user of the 24V setup. Dont want to be messing around with balance chargers.

Tab welder would cost $80usd, mine cost about that, but I soldered my own pcb board from
http://avdweb.nl/tech-tips/spot-welder.html
but looks like he has got something new
http://avdweb.nl/arduino/hardware-interfacing/spot-welder-controller.html
 
markz said:
ru.nkon.nl in the netherlands uses a tab welder. Key search term "Tab Welder" or "Tab Welding"

Soldering to tabs are easier and less heat damage because you are heating up the tab and not the metal on the can itself.

Its still a bit of work even with the tabs on there from nkon. But the work isnt all that much.
All I do is go to Home Depot and buy some 10/2 household wiring with solid conductor not stranded, it come with 2 conductors that are 10awg and a third bare wire that is 12awg, use 10awg for series, and 12awg for parallel. Strip the two 10awg and cut as needed.

24V is only 6S or 7S then if you use PF 18650 cans then they are 2.9Ah with 10A discharge. So say 15Ah is 5P, 45 cans in total. A decent soldering iron, some solder, wire strippers.

I'd say an average person with soldering knowledge could do it in, 2 or 3 hours.

It just saves a bunch of money that could go towards extra capacity in the battery, decent BMS which is what a plug & play would require for the user of the 24V setup. Dont want to be messing around with balance chargers.

Tab welder would cost $80usd, mine cost about that, but I soldered my own pcb board from
http://avdweb.nl/tech-tips/spot-welder.html
but looks like he has got something new
http://avdweb.nl/arduino/hardware-interfacing/spot-welder-controller.html

Thanks I am quite interested in trying to make a 36v pack, are you saying it's done without adding nickel strips to the pre-soldered tabs and soldering the wires and BMS up is the body of the work aside from layout, planning and enclosing the pack?
 
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