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I needto rebuild a 24v-10Ah li-ion battery for a Schwinn Tailwind Ebike(YouTube)


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03-26-16, 07:23 AM   #1 (permalink)  
I need to build an Ebike battery-Help me answer

Will 8 x 3.7v-9800mAh 18650 cells paralleled together give me 29.6v-9.8 Ah power?
Please help, Otis

 
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03-26-16, 07:47 AM   #2 (permalink)  
no wiring in parallel only increases the amp hours so while you could have 9.8 ah it would only be 3.7 volts wiring in series increases the voltage but doesn't increase the ah you would have the same ah as a single cell.

 
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03-26-16, 08:40 AM   #3 (permalink)  
Thanks, I'm a novice, So how many and wired how to get 28-24v - 9.8 Ah? and wherecan I get REAL 18650 for cheap Thank you,
Otis

 
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03-26-16, 08:47 AM   #4 (permalink)  
So, 8 in series would give me 24-28v 9.8 Ah? and where can I get REAL 18650's for cheap?
Thank you,
Otis

 
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03-26-16, 08:49 AM   #5 (permalink)  
Or use two of these in series. Gives you 24 volts at 12 ah, which is acceptable. About $100, and ready to run. https://www.batteriesplus.com/batter...750/sla12=12f2

 
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03-26-16, 09:14 AM   #6 (permalink)  
There is an inherent problem with using lithium cells in series..... charging them.
Most custom packs have thermal sensors in them that monitor the cell temperatures for overheating.


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03-26-16, 02:25 PM   #7 (permalink)  
Too much weight I want it under 6 pounds

 
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03-26-16, 05:13 PM   #8 (permalink)  
Most 18650 have a capacity of less than 3000 mAh so hooking them up in series will provide only about 1/3 the capacity you want. As for "real" you'll have to define what real is to you. There are a great variety of 18650 batteries which is further compounded by those having a built in protection circuit.

 
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03-26-16, 05:25 PM   #9 (permalink)  
Since you are trying to create a lithium battery pack I strongly suggest you take a break and learn the in's and out's of the various lithium battery technologies. They are a totally different technology than the alkaline or lead batteries you might be familiar with. They have very specific charging requirements that relates directly to their safe use.

 
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03-26-16, 05:31 PM   #10 (permalink)  
Isn't this a duplicate of http://www.doityourself.com/forum/al...me-answer.html

 
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03-26-16, 05:32 PM   #11 (permalink)  
Yes, it's the third duplicate.
Please stop posting duplicates of your question. Only one is needed. More than one is neither needed nor allowed.


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03-26-16, 06:00 PM   #12 (permalink)  
Yes I do have the BMS with LED meter from the original lithium ion battery, question is how do I get more amps from 8 18650's. .What's the alternatitive Li-ion or Li-po cell to use and wheredo I get it? Real means not blanks from China.
Otisyou,

 
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03-26-16, 06:15 PM   #13 (permalink)  
Sorry, I'm new at this . . .

 
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03-27-16, 05:47 AM   #14 (permalink)  
You can not get more capacity from eight 18650 batteries. When you say eight 18650 you just specified your limit. To get more capacity you can go with more batteries or use something other than 18650's.

18650 batteries in general hold less than 3000mAh. Some hold more and some less. The problem with 18650 is that there are many brand names and their specs are often false. It's common for imported batteries to have greatly inflated specs. So, you may see some labeled as having 5'000mAh capacity but in reality they may only be cheap cells containing 2'000mAh.



Yes, you can use a different battery technology. LiPo would give you the most capacity for the lightest weight. You would need a different charger and you would need to treat the batteries properly. LiPos typically have no internal protection and no protective case and they must be properly charged. LiPos are extremely powerful and with a lot of energy stored in something so small there is danger. They can be used safely but they are a totally different technology and must be treated properly especially regarding charging.

 
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