mr.electric
10 kW
I decided to make a pack for the little eike I have.
Making an A123 pack
- Thread starter mr.electric
- Start date
mr.electric
10 kW
This is the stock Pb pack. 36v 7 -10 ah (guessing on ah rating). Also my donor A123 cells this is one of three 11p2s packs.
I want to build a pack that is close to 48v. I guess 4p14s would be 49v and 9ah. I will have to see what will fit in the box and decide how many cells I want to devote to this project. I am guessing that the ah rating on A123 does not compare to the Pb ratings. I think the A123s will be good for close to double the range as Pb with the same ah rating due to the inefficiency of Pb getting hot during a 45 minute discharge and all the extra vehicle weight you have to lug around.
I want to build a pack that is close to 48v. I guess 4p14s would be 49v and 9ah. I will have to see what will fit in the box and decide how many cells I want to devote to this project. I am guessing that the ah rating on A123 does not compare to the Pb ratings. I think the A123s will be good for close to double the range as Pb with the same ah rating due to the inefficiency of Pb getting hot during a 45 minute discharge and all the extra vehicle weight you have to lug around.
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Icewrench
10 kW
Search for evg 123 on page3 these days. That`s my first effort at a pack build.
With a 36 volt factory built e bike I`ve kept the voltage in the 36 volt range.
Using a 4p 12s layout that`s all that would fit in the battery box.
Accessories like lights and controller might not like higher voltage. Good luck
With a 36 volt factory built e bike I`ve kept the voltage in the 36 volt range.
Using a 4p 12s layout that`s all that would fit in the battery box.
Accessories like lights and controller might not like higher voltage. Good luck
mr.electric
10 kW
Cutting the strips of cells into 3p2s pieces.
mr.electric
10 kW
Finished pack should fit nicely into the stock battery box.
mr.electric
10 kW
After cutting the long strings into smaller chunks I put them back into the cell frames. I am holding an experimental jumper. I hammered a piece of solid copper wire flat but it was not flexible. I will look for copper tape. I think the garden store has a product designed to wrap around the base of plants to keep snails from climbing up. If that is too thin I will just go to a metal supply house. I am imagining something similar thickness to a piece of paper and about 1 inch wide as a perfect connector.
mr.electric
10 kW
An almost finished 24v pack. This will be half of my pack. I just have to add sense wires. I think I will uses solid core telephone cable to bring the sense wires out of the pack. I want to mount the BMS board out of the battery box. I still have not found an appropriate multi pin plug for the sense wires. I could just break down and buy some mini fit molex plugs but I don't like them too much. Maybe I will use R/C car sense wire plugs. The R/C chargers and plugs max out at 6 cells in series. I have a 14s3p pack so I guess I would need at least 3 sense wire plugs. I will try to order one of the boards that this forum developed but I want to be able to try the fancy R/C charger too since my friend bought one and I could easily borrow it.
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slayer
1 kW
mr.electric said:
Hi M.electric,
i am surprised no one asked where you got those packs 11p2s... also what are the 6 little boxes in the pics?
i see in the quote i put you say :i have a 14s 3p pack so i guess i would need at least 3 sense wire plug ...
it is the contrary you should have a sense wire for every series you put ...so you would need 14 sense wire
slayer
1 kW
Ok i just figured what the boxes are, 6 6volts pb right?
can i give you another suggestion for the balancing
there are some 8 plugs like that that are available that you could attach to the boxes and use some voltphreaks charger and only use 7 of them of course plugging plus to each plus of the 3p and minus to each 3p also and then you could also monitor them
can i give you another suggestion for the balancing
there are some 8 plugs like that that are available that you could attach to the boxes and use some voltphreaks charger and only use 7 of them of course plugging plus to each plus of the 3p and minus to each 3p also and then you could also monitor them
GGoodrum
1 MW
If you are planning on using a 48V SLA-type charger, you need to use a 16s a123 configuration. Generally, 4 LiFePO4 cells = 6 SLA cells, for charging. Each SLA cell has a nominal voltage of 2.0V, but gets charged to 2.45V. For a 24-cell 48V SLA setup, the charger tops out at 2.45V x 24, or 58.8V. Your a123 cells have a nominal voltage of 3.3V and get charged to 3.65V, so 16 in series needs a charge limit of 58.4V, so the SLA charger can be used, in most cases. If you use 14s, you will need a charger that puts out 14 x 3.65V, or 51.1V. Your best bet, if you keep this at 14s, will be to find a surplus 48V lab supply with a trimmable output with a 10% range.
-- Gary
-- Gary
Zoot Katz
100 kW
Here's my two Canadian pesos contribution:
I'd strongly, in no uncertain terms, recommend against using solid wire in any situation where vibration is a factor.
FWIW.
I'd strongly, in no uncertain terms, recommend against using solid wire in any situation where vibration is a factor.
FWIW.
mr.electric
10 kW
I forgot that I have a few deutsch connectors. They should work pretty well. I will also use braided wire not solid core.
This page shows the connector I have. I am pretty sure I have a 16 pin version.
file:///Users/bill/Desktop/Green%20Gears/Endless%20Sphere/Deutsch%20DTM%20Series%2012-Way%20Connectors.webarchive
This page shows the connector I have. I am pretty sure I have a 16 pin version.
file:///Users/bill/Desktop/Green%20Gears/Endless%20Sphere/Deutsch%20DTM%20Series%2012-Way%20Connectors.webarchive
Doctorbass
100 GW
slayer said:
+1
Where these cells parts come from?!! I like the OEM 6 cell spotweld Z shape link.. where it come drom too!?
Doc
mr.electric
10 kW
The cells come from my ties with an automotive battery testing program, and I only got enough "throw aways" to make two bike packs. Unfortunately I cannot get any more.
Doctorbass
100 GW
mr.electric said:
Just to know more about, can you give us max info on that automotive battery program?? ..
Doc
slayer
1 kW
Nice battery holder too Mr electric do you think you could get some of the holder?
mr.electric
10 kW
mr.electric
10 kW
I just need to add the main pack plug and wires. Two half packs done. I guess I will need to add more cells to use the 48v pb charger I have. I am currently at 14s3p. I will add 6 more cells to get to 16s3p. I could not find any good copper tape so I just stuck with wire jumpers to make the pack. Sorry I do not currently have any extra cell holders.
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MitchJi
10 MW
Hi,
Are the cell holders a custom part or are they available someplace?
Thanks!
Mitch
mr.electric said:
Are the cell holders a custom part or are they available someplace?
Thanks!
Mitch
mr.electric
10 kW
Only a few cell holders exist. They are not as good as they appear on the pictures. Only a special shaped jumper will not interfere with the shape of the cell holder.
MitchJi
10 MW
Hi Doc,
I think we can safely deduce that they come from Hymotion Phev kits:
http://endless-sphere.com/forums/memberlist.php?mode=viewprofile&u=91
We can also see that they use a lot of cells in parallel.
Doctorbass said:
I think we can safely deduce that they come from Hymotion Phev kits:
http://endless-sphere.com/forums/memberlist.php?mode=viewprofile&u=91
We can also see that they use a lot of cells in parallel.
CGameProgrammer
10 kW
Can you post better pictures of those deutsch connectors and whatever receptacles you're using for them? I may buy those. They look like a good 12-pin connector, albeit pricey.
