Homemade Battery Packs

I couldn't fit the Battery Clearing House packs on my bike, and I couldn't store them either in my battery safe (cinder bnder blocks) so I eventually cut them in half. The balance wires were in circuit boards, one on three sides of the battery. The battery itself was diffificult ti understand. The last two groups were arranged six cells in a line, with cross connectivity on the circuit boards.

I eventually made my cuts, and only lost the balance traces to 4 cells. which I re-did with wires. I was able to slice thru the circuit traces too w/o leaving any cells short circuited. Whew. I saved the original BMS, and didn't spend any extra money, resulting in a more compact 10S-3P pack using NCR18650BD's.

Long Battery.JPG

Tha packs came with half cases. I destroyed the first one, learning how it was attached (screws glue), and saved the second one to cover the circuit boards. Hence it's well protected.

W1050520.JPG
 
.
...
Impulse buy

51.8V  35Ah.jpg

Could not pass it up.
Perfect for my 48V 1500w.
Good thing I jumped on it, got the last one!
3C continuous discharge,
70% charge in <30 minutes

May be more available as they test each item in batches.
I know, "Homemade" doesn't ethically apply, but technically, I need to add a BMS and put in a tool box\shell.

Nice job docw009 !
 

Someone told me to buy one of those when they came up last week. They sold fast.

About time you started messing with *real* batteries and not that cylindrical cell junk.
 
DogDipstick said:

Someone told me to buy one of those when they came up last week. They sold fast.

About time you started messing with *real* batteries and not that cylindrical cell junk.
Tell that to Tesla?
 
DrkAngel said:
.


Tell that to Tesla?

Nah we turned down their job offer.

Not enough money.
 
DogDipstick said:
DrkAngel said:
.
...
Impulse buy

file.php


Could not pass it up.
Perfect for my 48V 1500w.
Good thing I jumped on it, got the last one!
3C continuous discharge,
70% charge in <30 minutes

May be more available as they test each item in batches.
I know, "Homemade" doesn't ethically apply, but technically, I need to add a BMS and put in a tool box\shell.

Nice job docw009 !
Someone told me to buy one of those when they came up last week. They sold fast.

About time you started messing with *real* batteries and not that cylindrical cell junk.
Tell that to Tesla?
 
Expecting delivery Monday.
Anticipated range based on previous data:
48V 10Ah Lithium battery = 480Wh
10mph = 46 miles range - 10.4Wh/mile
15mph = 30 miles range - 16Wh/mile
20mph = 20 miles range - 24Wh/mile
25mph = 13 miles rang - 37Wh/mile
30mph = 8 miles range - 60Wh/mile
based on Wh, range will be 383%
just for convenience, I'm calculating at 4x (within 5%)

51.8V 35Ah Lithium battery = 1840Wh
10mph = 184 miles range - 10.4Wh/mile
15mph = 120 miles range - 16Wh/mile
20mph = 80 miles range - 24Wh/mile
25mph = 52 miles rang - 37Wh/mile
30mph = 32 miles range - 60Wh/mile

Great range!
4 hours @ 20mph cruisin"
2 hours @ 25mph commuting
1 hour @ 30mph with "traffic" (greatly extended if I can slip in behind some "blocker")
(Bike @ 14s is 40mph capable)


I only have a 5A 51.8V charger at present ≧ 8 hour charge time

50A charger = 70% charge in <30 minutes (but draws ~25A 120AC and will blow standard breakers)
so would need:
≦40A 51.8V for a 20A circuit = 57% charge in 30 minutes
≦30A 51.8V for a 15A circuit = 43% charge in 30 minutes
 
I will start with my 5A charger but will likely series a 48V 12.5A with a 12V 12.5A MeanWell Mega-Mod, for rapid charges.
Hmmm ... likely parallel with my 5A for 17.5A charging

DrkAngel said:
51.8V 35Ah Lithium battery = 1840Wh
10mph = 184 miles range - 10.4Wh/mile
15mph = 120 miles range - 16Wh/mile
20mph = 80 miles range - 24Wh/mile
25mph = 52 miles rang - 37Wh/mile
30mph = 32 miles range - 60Wh/mile
.

Gas at $5/gallon
Electricity at $0.10/kWh
At 20mph = 42 miles/kWh
Cost = 50kWh per gallon of gas
for 50kWh x 42 miles/kWh = 2100 miles per gallon cost equivalent
 
Getting back to "Homemade Battery Packs" lithium pouch cells are the darlings of the EV Industry. Beginning to look like salvaged EV pouch cells are also the darlings of the more adventurous 100A Speed Demons (with pedals :wink: ).
DogDipstick said:
About time you started messing with *real* batteries and not that cylindrical cell junk.
DrkAngel said:
Tell that to Tesla?
Beginning to look like Tesla is putting the wrong eggs in its basket (even with its 4680 eggs)? E-bike battery packs and POWER Tool battery packs are now available using Li pouch cells ...

Flex-Stcked-Lithium-Batteries-01-800x800.jpg


THE BOTTOM LINE
The additional power potential coming from smaller batteries is really exciting. When you add in faster charging and a much longer service life, the transition to lithium pouch cell batteries makes a lot of sense and opens the door to all-new levels of performance.

DD should start a lithium pouch cell DIY project thread (spot-welding not needed) for 12S-14S DIYers. Builders that are satisfied using no more than a 30-40 amp Controller. Adhering to the following restriction (As-Best-As-Possible - :wink: - with pedal assist) ...

  • Class 3: A bike with a motor that provides pedal assistance and can reach 28 mph

The Harley-Davidson Serial 1 e-bike rated speed is 20mph with pedal assist. Battery design similar to that of the HD Live-Wire ("automotive level custom battery"). Assume the Serial 1 comes with an EV lithium pouch cell battery. The Serial 1 Rush version can go up to 28mph.

Is DD's vision - salvaged EV cells (e.g. Battery Hookup) primarily for 100A - Speed Demons ?
 
LG LGX P33 - 60A - 33Ah - Li-Ion High-Drain Pouch (flat-pack) Cell ... $10 each
https://www.batteryclearinghouse.com/products/lg-lgx-p33-60a-33ah-li-ion-high-drain-pouch-flat-pack-cell

p33_1_500x.jpg


Max Charge 16A / Max Discharge 60A / FULL 4.2V / FULL Discharge Voltage: 3.0V
Dimensions: (L)27cm (including 4cm for tabs) x (W)9.75cm x (T)1cm - Wt: 1.25lbs

12S1P = $120 -- DIY two 6S1P for Y-charging & placement convenience on bike
Each 6S1P outer enclosure approximate dimensions -- 15"x 5"x 4.0" (depending)

NOTE: Why is the good stuff already ... SOLD OUT ... ready to place order :thumb:
Where's next best buy for a good enuf LG 30A-60A lithium pouch cell DIY build?
 
DrkAngel said:
dirt huffer said:
Thanks for the awesome Wiki!
QuNick question... what program do you guys use to determine size/shape/cell count/orientation of 18650 cell pack? I have a full suspension frame and need to get creative to pack as many cells in it as i can

.

No known "programs"
I know this is a couple years after this post but....I am aware of this site which will help. e4bike battery shape configurator. https://e4bike.ru/page/battery-shape-configurator?lang=en
 

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Got my 20 - 6 packs of Lipo. 1 mated pair of cells was bad.
Still that is $40 for nearly, a 1KWH battery pack!(.96KWH)

Took 1 - 11.1v - 4.32ah brick, charged it to the nominal 12.6v, hooked it, with an amp meter, to a 12v 250w leaf blower, it surged to 20 amps, then settled to 11 amps, as leaf blower attained speed.
About 15 seconds later, one of the built-in fuses, blew.

Fuse is easy to bypass, but my 25.9v pack will have 6 banks of these bricks, or about 120amp surge & 60+amps continuous capability!
Present bike's, noticed, surge usage was barely 30 amps, continuous is about 15.

And! ...
I scraped the scummy SLAs out of an EZip pack, and was able to stack in almost 26ah of Lipo! (25.92ah)
Or ... could fit 17.28ah @ 37v.
A little better than the 24v 6ah usable, provided by the OEM SLAs!

Weather is lousy, so I'm charging - testing -discharging - more testing, to confirm, best cells, before assembly.
Will keep everyone posted!
All the links appear broken, unless I'm broken LOL
 
The conversion early this year from the old PHPBB forum software to the new Xenforo software didn't correctly migrate the links in many (most) posts. Hand editing them all is probably never going to happen, so unless a tool can be written to do it automagically, the best I can recommend is that for content like this is to use the archived version of the original forum here:

to find the same thread. If you copy any of the links that is "broken" and paste it into Notepad or other text editor, you can add "-old" to the "forums" part of the link, like below:
-old/viewtopic.php?f=14&t=26383&p=1180493&#p1180493
then copy that new link into your browser and go there to get to the archived thread. From there you can go back to the beginning of the thread and the page of links, etc.
 
The conversion early this year from the old PHPBB forum software to the new Xenforo software didn't correctly migrate the links in many (most) posts. Hand editing them all is probably never going to happen, so unless a tool can be written to do it automagically, the best I can recommend is that for content like this is to use the archived version of the original forum here:

to find the same thread. If you copy any of the links that is "broken" and paste it into Notepad or other text editor, you can add "-old" to the "forums" part of the link, like below:
-old/viewtopic.php?f=14&t=26383&p=1180493&#p1180493
then copy that new link into your browser and go there to get to the archived thread. From there you can go back to the beginning of the thread and the page of links, etc.
Thanks. ill have a go later, sorry to be a pain, but I didn't think I was doing it wrong, and someone else just confirmed it was FUBAR a technical term I think for not at optimum working efficiency LOL,

On 18650 cells, got ten 29E cells from of a bucket of water (Now thanks to you I know why they were in there LOL).... All at 0v, open circuit, and one had a hole in. Couldn't resists, all are now apparently working perfectly, even the one with the hole in. Photo attached. Did think of writing it up and posting it, but being someone who grew up playing in bomb sites of WW2, syphoned aviation fuel from abandoned planes to make molotov cocktails (there were quite a lot that had managed to crash land without exploding, and still littered the country side), could even scavenge live ammo from them, put it is a bit of cast iron gas pipe and hit the end with a hammer and nail and shoot holes in the planes, these formative years resulted in me being a bit less risk averse, than many people now are (who now know better, and are taught not to do such things). So I decided not to write up how to fix totally dead li ion, open circuit cells that have been submersed for some time and may have a hole in, as it is not without risk. LOL..... But appears to work, Freezing defrosting appears to solve the open circuit issue, NiCad charge wakes them up (but they get hot one burnt my finger quickly getting it out of the charger) then Li-ion charge them. Cycle them a few times and back to 4.2 v. The one with the hole fixed with my gas stove soldering iron , and some fine copper wire in the solder, like fiberglass (solder wont cover the hole)

Keith

As an after thought, impossible question really but would value your opinion, Having built one 18650 battery which was eventually easy and didn't take long, IF I uses my recovered cells I have enough to build an identical battery. So first, should I actually use them in a battery now they appear as good as new (but obviously are not) If so would you stick them all in one parallel group, so if they turn out to be less good its easy to replace the entire group, or mix them in as if mixing in other spec cells, eg one per group. Finally if not was thinking of buying 2500mah Molicel cells as they appear a pretty good match on that battery comparator you showed me, so I would put one per // group, and thus have a few samsung 29E left over including all the fixed ones.

Any comment welcome.
 

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On 18650 cells, got ten 29E cells from of a bucket of water (Now thanks to you I know why they were in there LOL).... All at 0v, open circuit, and one had a hole in. Couldn't resists, all are now apparently working perfectly, even the one with the hole in.
I really really recommend putting them back in the bucket and getting rid of them.

Cells that (for whatever reason) have been discharged below their low-safe-limit can be damaged inside in ways that can lead to a fire. Since you cannot know if they are damaged, or how, without destroying them in disassembly and examination (probably with some form of microscopy to find the faults), they should be considered unsafe to use for any application at all.

The damage to them could create an internal catastrophic failure at any time, under any conditions, in any usage.

Physical damage of any kind to any cell (of any format) also qualifies for this, as you can't know what damage is like inside, and whether there is a chance of shorting layers of it together, etc., and any of the damage could cause a fire, at any time.

They might work perfectly for years with no issue.

They might catch fire tonight while you're asleep, start spewing flaming cell cores like hopping fireworks, and set fire to the neighborhood....

You just can't know.... :(


It's bad enough that there are plenty of new unknown-quality cells out there that you can't know if they have internal factory defects because the manufacturers aren't doing QC, or the QC rejects (of even good manufacturers) are sent to be recycled for materials but instead are resold by quick-buckers....
 
I really really recommend putting them back in the bucket and getting rid of them.

Cells that (for whatever reason) have been discharged below their low-safe-limit can be damaged inside in ways that can lead to a fire. Since you cannot know if they are damaged, or how, without destroying them in disassembly and examination (probably with some form of microscopy to find the faults), they should be considered unsafe to use for any application at all.

The damage to them could create an internal catastrophic failure at any time, under any conditions, in any usage.

Physical damage of any kind to any cell (of any format) also qualifies for this, as you can't know what damage is like inside, and whether there is a chance of shorting layers of it together, etc., and any of the damage could cause a fire, at any time.

They might work perfectly for years with no issue.

They might catch fire tonight while you're asleep, start spewing flaming cell cores like hopping fireworks, and set fire to the neighborhood....

You just can't know.... :(


It's bad enough that there are plenty of new unknown-quality cells out there that you can't know if they have internal factory defects because the manufacturers aren't doing QC, or the QC rejects (of even good manufacturers) are sent to be recycled for materials but instead are resold by quick-buckers....
IRONICALLY

I was actually thinking while I had a gut feeling this was not a good idea, but IF BOUGHT THESE USED, not knowing their history, I would of utested them and used them without hesitation. That kinda makes you wonder about buying used cells doesn't it.
 
I really really recommend putting them back in the bucket and getting rid of them.

Cells that (for whatever reason) have been discharged below their low-safe-limit can be damaged inside in ways that can lead to a fire. Since you cannot know if they are damaged, or how, without destroying them in disassembly and examination (probably with some form of microscopy to find the faults), they should be considered unsafe to use for any application at all.

The damage to them could create an internal catastrophic failure at any time, under any conditions, in any usage.

Physical damage of any kind to any cell (of any format) also qualifies for this, as you can't know what damage is like inside, and whether there is a chance of shorting layers of it together, etc., and any of the damage could cause a fire, at any time.

They might work perfectly for years with no issue.

They might catch fire tonight while you're asleep, start spewing flaming cell cores like hopping fireworks, and set fire to the neighborhood....

You just can't know.... :(


It's bad enough that there are plenty of new unknown-quality cells out there that you can't know if they have internal factory defects because the manufacturers aren't doing QC, or the QC rejects (of even good manufacturers) are sent to be recycled for materials but instead are resold by quick-buckers....
 
I did suspect that,:cry: but hoped:rolleyes:. So that brings me back to a Q I asked. I got 45 good Samsung 29E cells same as the ones in my first successful pack (Which I'm OTM about) so would have liked to build identical one, but Im 5 short (and just realised if I wouldn't use my repaired cells myself then I cant even sell them either.... Bummer :mad: ).

BUT 2500mah 3.7v Molicel look like a reasonable match, bearing in mind my blue samsungs are not new, they have been used for a couple of years. Looking at them both on the battery comparator that you showed me the characteristics look similar, so how about one of them in each // group of 5 to make a 10 x 5 36v battery.

I can but 10 of them new for £25 on e-bay.

Keith

PS..... After seeing several mentions of QC that I did not immediately get ??? Now realised QC is probably Quality Control right? So these smaller dealers are probably selling what in the UK we would call "seconds" basically QC rejects that are useable, and usually under UK law QC Rejects have to be CLEARLY marked as "seconds" or "Graded Stock", and in all other industries they are so marked. Even market traders will sell "seconds" and usually even they go as far as putting an arrow pointing at the imperfection. (I bought a range cooker with a scratch on the side panel for about a third of its full retail) And once fitted you couldn't see the scratch.... so bargain, but the fault was clearly marked. Reading between the lines I'm guessing in this industry, people buy the "seconds" and then just sell them as though they were perfect "Called Passing Off". Which is a criminal offence in the UK, but catching culprits and proving it is difficult. BUT does happen, but usually only by the time it has become big business. Then our Trading Standards get of their A**** and make the Police get of theirs as well, THEN FINALLY there is a "Multi Million Pound Crime Ring Smashed"

PPS..... We dont appear to have anything like Battery Hookup here (WELL NOT THAT I COULD FIND), and sadly shipping cost from the US are prohibitive I checked with them. There are lots of smaller dealers on e-bay, sadly there isn't really any way to tell how good they are, obviously even the feedback score doesn't really tell you, because when you buy something. If it arrives quick and looks perfect out of the packet, and immediately appears to work, so then you leave good feedback...... Which is fair enough...... But once you leave feedback it cannot be changed, so if for example you bought some "NEW CELLS" and if one burst into flame and burnt your house down the following week.... Your feedback would still and forever more say "GREAT, product great price etc.
 
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