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Old 08-23-2016, 03:00 AM
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Default Electric e zip 750 mod

Going to start building a scooter battery from scratch using lithium ion cells putting them into packs of 5s 4p .why to replace the dreaded yet historic lead acid battery .lithium ion weighs a fraction of what a sla battery weighs .longer lasting and less weight more recharge cycles then sla .Th bad part is there very temperamental they tend to explode or catch fire .Power source for this electric scooter will be 40 18650 size batteries that I have recycled and tested with a IMAX b6 (smart hobby charger) .they will need to be all soldered together that's 80 total connections .I should be able to get 20-25 ah with these batteries .All the batteries in this will be recycled from old bad laptop batteries that everyone tends to throw away .Going Green pictures coming soon

---------- Post added at 04:00 AM ---------- Previous post was at 03:53 AM ----------

After this I have to figure out what to do with 600 4/3a 4500mah NiMH cells that are 1.2v .To low of a voltage compared to the 3.7v lithium ion .
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Old 08-23-2016, 07:59 AM
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uhm battery tabs are typically welded, not soldered...

But be very careful, as you said.. you don't want to overheat a cell and stay anywhere near it

Also, take care of the physical layout as well. and use thermal fuses to protect each of the 4 parallel packs.

'sid

PS you sure all of the cells are of the same capacity?
since you cannot use different capacities in series (you'll end up with the lowest of them as your total capacity for the stack)
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Old 08-23-2016, 08:09 AM
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Quote:
Originally Posted by itsid View Post
uhm battery tabs are typically welded, not soldered...

But be very careful, as you said.. you don't want to overheat a cell and stay anywhere near it

Also, take care of the physical layout as well. and use thermal fuses to protect each of the 4 parallel packs.

'sid
PS you sure all of the cells are of the same capacity?
since you cannot use different capacities in series (you'll end up with the lowest of them as your total capacity for the stack)
I grouped them together in parallel making sure that they where no more then 200mah difference in each parallel set biggest being 2.2 and smallest being 1.7 ah .But because there in parallel they act as one big battery .BMS battery management system keep track of voltages temps .Yup there usually spot welded but soldering can be used if you have a steady hand and a little skill and you don't drop solder on your self .I have a metal tea pot I use for bad cells just in case they go into thermal runaway they can vent in a all metal container with no air getting in to start a fire .
PS.I forgot I have 16 lipo cells to lol
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Old 08-24-2016, 12:51 AM
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Lipo fire! Not that you will be driving a nail into a Lipo Battery but the fire will NOT be put out without expensive fire suppression tools. or as sid calls them "STD" supressors.
Amazing
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Old 08-24-2016, 04:16 AM
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Well Bird.....

you cannot just put it in a sealed metal container.. that's as effective as closing your eyes.
LiPos bring their OWN oxygen, that's the main reason std fire estinguishers fail.
They also burn hot enough to burn through many metals.. a teapot is certainly not sufficient, I doubt an ammo box is.

math isn't exactly working out again either...
but you know, just go for it..
just do it outside ten feet from anything that could catch fire.

I've seen a much braver man than you are just recently welding a tap onto a single LiPo cell...
with his home made tack welder.. an odd setting and the sleeve catched fire.
And you could hear in his voice he's scared getting hectic and all..
because he KNOWS.

Sorry Bird, you do not!
what you might think is bravery or sufficient precaution is in fact just lack of knowledge;
a teapot.. really?

'sid
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Old 08-24-2016, 05:51 AM
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Li-on lithium ion -lithium polymer I'm using Lion not lithium polymer .All good things come with practice as so knowledge is learned through mistakes I'm sure Nicola Tesla has fried him self more then once had a few small fires don't shoot me down just yet .I have just finished my first pack of 20 has 16.8v fully charged and 7.2 ah pack .5 series 4 parallel 4.2v X 4=16.8 v
There is a guy in YouTube using the same batteries to power a VW bus (samba) it's a cool idea and I wanted to share what I was doing with everyone on the forum .

---------- Post added at 06:51 AM ---------- Previous post was at 06:48 AM ----------

Quote:
Originally Posted by chancer View Post
Lipo fire! Not that you will be driving a nail into a Lipo Battery but the fire will NOT be put out with out expensive fire suppression tools.
Amazing
That is dangerous don't get me wrong but that is a good way to discharge them before you throw them away .granted salt water in a bucket is a better idea much safer .
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Old 08-24-2016, 07:46 AM
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Quote:
Originally Posted by BirdFanatic View Post
Li-on lithium ion -lithium polymer I'm using Lion not lithium polymer .
Sad...I kinda expected that Bird...

LiPo ARE Li-ion batteries just as LiCoO LiTiO or LiFePo...

You know what I said about lack of knowledge...
You know you just proven that?
Do you even KNOW what a Polymer is?

If you read Li ion on the battery.. it could still be a LiPo cell .. but it doesn't matter since the danger remains the exact same,
no matter what kind of electrolyte is being used..
in fact a polymerised electrolyte is actually a tiny bit safer.

Anyways, read at least about cell matching and why the manufactures do that
(short story: the weakest cell in a block will overheat when being charged.)

And maybe why modern day laptop batteries contain nearly as many chips as the laptop they're powering

But, again.. please proceed..
just please don't hurt yourself in the process (or while using that frankenstein battery afterwards)

that's all I'm asking.

'sid
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Old 08-24-2016, 09:11 AM
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Thank you for looking out for me this is my first time building anything .If we go back a year ago I used to buy and sell.This is a big step away from that

I'll play it safe no more tea pot lol I'll throw the **** thing outside as if it where a grenade and someone pulled the pin.Making sure it's not around anyone or anything that can catch fire .

Lipos have a soft case that are very vulnerable to being punctured.
So I have 5 18650 in parallel let's say I have written there mah on them using the smart charger /discharger I group them and add the total mah of the 5 there are 4 rows of 5 parallel batteries .Then I add up the other 4 and make there mah as close as possible to the 1st group .The smart charger helps me weed out the bad batteries if they don't reach over a certain mah I don't use them for my pack .I do not throw them away either I use them for flashlight batteries. I wouldn't want to use a cell that should have 2200mah brand new but has 800 mah a cell with 1700 mah is good .
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Old 08-24-2016, 09:51 AM
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Quote:
Originally Posted by BirdFanatic View Post
I'll play it safe no more tea pot lol I'll throw the **** thing outside as if it where a grenade and someone pulled the pin.Making sure it's not around anyone or anything that can catch fire .
That's what I wanted to hear
play safe... don't take a risk if a cell get's uncomfortably hot.. act quick.. when in doubt: RUN!

Quote:
Originally Posted by BirdFanatic View Post
Lipos have a soft case that are very vulnerable to being punctured.
not necessarily!
Quote:
Originally Posted by BirdFanatic View Post
So I have 5 18650 in parallel let's say I have written there mah on them using the smart charger /discharger I group them and add the total mah of the 5 there are 4 rows of 5 parallel batteries .Then I add up the other 4 and make there mah as close as possible to the 1st group .The smart charger helps me weed out the bad batteries if they don't reach over a certain mah I don't use them for my pack .I do not throw them away either I use them for flashlight batteries. I wouldn't want to use a cell that should have 2200mah brand new but has 800 mah a cell with 1700 mah is good .
What now you said 4p 5s.. now it's 5p 4s...

typo?

Anyways.. that's the wrong way around!

you want to stack similar cells in series,
and pack these in parallel.

Not the other way around.

in series all cells try to hold a similar charge (total charge is set by the weakest cell)
in parallel charges add up (total charge of the individual stacks of cells in series)
And while this too SHOULD be stacks of similar charges..
in parallel it's the stacks resistance determining the amount of charge the stack will hold.
it's trying to self level ... (It cannot too well though... that's where all the microprocessing comes in)
So a stack can still overheat (hence I asked you to add thermal fuses to each stack)

BUT it's the safer approach since similar cells will heat up more evenly,
and a single thermal fuse (at the right tempsetting of course) is more likely to protect all cells in a stack even if it's only touching two or maybe three cells.

'sid
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Old 08-24-2016, 10:23 AM
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Quote:
Originally Posted by itsid View Post
That's what I wanted to hear
play safe... don't take a risk if a cell get's uncomfortably hot.. act quick.. when in doubt: RUN!


not necessarily!


What now you said 4p 5s.. now it's 5p 4s...

typo?

Anyways.. that's the wrong way around!

you want to stack similar cells in series,
and pack these in parallel.

Not the other way around.

in series all cells try to hold a similar charge (total charge is set by the weakest cell)
in parallel charges add up (total charge of the individual stacks of cells in series)
And while this too SHOULD be stacks of similar charges..
in parallel it's the stacks resistance determining the amount of charge the stack will hold.
it's trying to self level ... (It cannot too well though... that's where all the microprocessing comes in)
So a stack can still overheat (hence I asked you to add thermal fuses to each stack)

BUT it's the safer approach since similar cells will heat up more evenly,
and a single thermal fuse (at the right tempsetting of course) is more likely to protect all cells in a stack even if it's only touching two or maybe three cells.

'sid
First post says 5p 4s if I said anything differently it was a typo .I would take a pic but internet is as slow as dial up .
You said what I was trying to say you did a much better job at saying it .That is the way I went about setting everything up . I like the idea of a bms (battery management system) it adds extra safety .I might as well throw in a volt meter to the pack.
Thank you for the extra knowledge taking the time to share it with me . I will def be getting a bms board
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Old 08-24-2016, 04:53 PM
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Quote:
Originally Posted by BirdFanatic View Post
Going to start building a scooter battery from scratch using lithium ion cells putting them into packs of 5s 4p .,,,,,
Quote:
Originally Posted by BirdFanatic View Post
First post says 5p 4s ....
no it doesn't

'sid
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Old 08-24-2016, 07:43 PM
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Lol wow I did I can't believe I even looked at it to make sure I was saying the correct one .I am so sorry I didn't even catch that one even though I was staring right at it even double checked it to make sure I was saying the right thing .
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Old 09-04-2016, 05:16 PM
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Just finished my DIY spot welder. I am using a mot as the power source three wraps of 4 gauge insulated wire where the secondary coil should be . Just moved to California again sorry Nick I abandoned ya .
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Old 09-04-2016, 05:21 PM
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Quote:
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. Just moved to California again .
Your going the wong way!
Many leave few come back!
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Old 09-04-2016, 06:24 PM
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Lol grass is not green on the other side
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Old 09-14-2016, 07:27 PM
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here are a few pictures the green batteries are my first pack its 22.5v 4.5ah . the second pack was made of lithium ions is 25.2v and 1.7ah

This picture is of the scooter .I was at my max image limit so i posted the last picture on a different post.
Attached Thumbnails
IMAG0149[1].jpg   IMAG0150[1].jpg  

IMAG0151[1].jpg   IMAG0152[1].jpg  

IMAG0154[1].jpg   IMAG0155[1].jpg  

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Last edited by itsid; 09-14-2016 at 10:44 PM.
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Old 10-12-2016, 12:48 PM
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Well I gave up on this one but not without making a few things I needed like a 12v Battery for my Bluetooth boom box a solar battery bank I can use the packs I made with an inverter just in case the power goes out but it has not gone out in many years
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Old 10-12-2016, 03:47 PM
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Lets see this spotwelder of yours you made...
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Old 10-17-2016, 12:10 AM
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It's horrible looking but it works
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Old 10-17-2016, 11:03 AM
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OK.... lets see it........
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