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Discussion Starter #1 (Edited)
So I received this from a member, it would charge but still showed 9.6V across the terminals. So I hooked it up to my Li specific charger which ignored it with "broken connection" message. Tried hooking it up to a regular battery charger and still no luck or effort.

Since it's now dead I decided to cut it open and see if it's repairable or can me modified to be used in my track bike if it's not good enough for a road user maybe.

The BMS system obviously has inbuilt short circuit protection, lose items from under seat storage touched battery while going over a speed bump in town, causing bike to cut out instantly.

I'm thinking of de-soldering all the cell's to remove the circuit board at the top, then using copper plate links to re-solder into the configuration that will give me the correct voltage.
This should then charge ok on my charger I recon, and I can pop into the 2nd bike for track days or coaching.

What do you guys think ? Anybody done this before ?
I recon it should work the same as what the original Lithium batteries used on race bikes which had no BMS system or protection.

I wouldn't want to use it on a road bike with lights and lots of charging, but I think for my second track bike it should be ok ?
 

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Discussion Starter #5 (Edited)

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Okay so practical advice. I'm no battery expert but I do know this. The protection circuit is there for very important reasons. Among them are:
1. They keep the battery from charging above its safe voltage.
2. They keep the battery from discharging below its safe voltage.
3. They regulate the current draw so it is not higher than the battery can provide.
I think in any application, using a lithium ion battery without the proper protection circuit is dangerous and since they are prone to explode or catch fire, if one doesn't have the money to buy a new battery, one won't have the money to fix a burning bike. :stickpoke

Love you Dons. And I mean that in the most sincere and manly way. :)
 

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Discussion Starter #8 (Edited)
Okay so practical advice. I'm no battery expert but I do know this. The protection circuit is there for very important reasons. Among them are:
1. They keep the battery from charging above its safe voltage.
2. They keep the battery from discharging below its safe voltage.
3. They regulate the current draw so it is not higher than the battery can provide.
I think in any application, using a lithium ion battery without the proper protection circuit is dangerous and since they are prone to explode or catch fire, if one doesn't have the money to buy a new battery, one won't have the money to fix a burning bike. :stickpoke

Love you Dons. And I mean that in the most sincere and manly way. :)
Now that's better, thanks mate.

Ok, I've posted various threads with info on Lithium batteries in the past, so I'm well aware the affects and dangers of these cells.
I'm also well aware of the differences between the various Lithium batteries, which incidentally very few guys on this forum are, you know ...... Lithium Iron, Lithium Ion, Lithium Iron Phosphate .......etc.
I also know that only some of them have this inbuilt safety system, and that this particular system is not the same as used in say Ballistic, Shorai or the Racing batteries which I also have here.

Then there's the fact that many companies used to buy and supply the A123 Lithium Phosphate cells seperate, many people or companies used to and still use these to make up custom configurations for various applications. Google eBay and YouTube for info and construction versions, something like this -
http://www.ebikeschool.com/how-to-build-a-diy-electric-bicycle-lithium-battery-from-18650-cells/
It's watching this that has me wondering if I could save these cells in a similiar fashion. It will go into my bike, so no overcharging and other influences, it's just plain curiosity and thinking outside the box.

Therefore wondering if anybody else had done any work on these specific cells, successfully, without purposefully blowing them up.
These are obviously the "pouch" style cell's. http://batteryuniversity.com/learn/article/types_of_battery_cells
There is also BMS systems available very cheaply on eBay which is good for self installation if push comes to shove. http://www.ebay.com.au/itm/Battery-Protection-BMS-PCB-Board-w-Balance-For-4-Series-12V-60A-LiFePo4-Cell/162200869725?_trksid=p2045573.c100033.m2042&_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20131017132637&meid=02d4efa780a24325b53c24c96e10e631&pid=100033&rk=1&rkt=1&sd=162200869725
 

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IMHO, if there is a protection board out there on the cheap, it might be worth it from a strictly safety/no guessing perspective for only $14 AU.
 

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As long as the starter current is less than 120A, most of the protection ct's are orientated to electric vehicles, bicycles etc which don't have the large outrush currents encountered when cranking over a petrol engine starter motor.

FWIW I made a battery for my old Daytona 675 out of 8 A123 cells that lasted 2 1/2 years until I sold the bike, had no BMS and the cells were always pretty close to each other voltage wise.

Those pouch cells look easier to assemble than the cylindrical cells.
 

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Discussion Starter #12
As long as the starter current is less than 120A, most of the protection ct's are orientated to electric vehicles, bicycles etc which don't have the large outrush currents encountered when cranking over a petrol engine starter motor.

FWIW I made a battery for my old Daytona 675 out of 8 A123 cells that lasted 2 1/2 years until I sold the bike, had no BMS and the cells were always pretty close to each other voltage wise.

Those pouch cells look easier to assemble than the cylindrical cells.
Yeah they're very easy to make into a small package.
I'm just hunting around for a decent heavy duty soldering iron, my gas operated model is too light to handle that amount of solder.:)
 

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Keep the info coming folks, I am learning a lot and enjoying this conversation!

I would think, as others have said, that, as long as you monitor for voltage, you should be fine without the management systems.
 

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Donsy, have you thought of trying mini capacitor boost packs?
For what Frank ? I'm not looking to re-invent the wheel mate, or buy anything, just don't want to throw a good set of cell's away.
 

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Donsy thought you'd be interested if you haven't look that way. very cheap. a guy on youtube build one with 6 cells @$8 each. really cool , a fraction of the size & weight of the car batt he replaced. the cells are the size of D cell batteries. see if you can find the video. my link sharing is for shit but you know that. GL

anyone who sees this is going to like it. might not be great for every day but track day bike oh yeah
 

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Just found a YouTube video where an Optimate charger brought back to life several dead or thought to be dead motorcycle lithium ion batteries!!! Looks like they can go into a sleep mode and the internal circuitry wouldn't allow them to recharge.

This is also a problem with cordless drills & cell phones.
 

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Just found a YouTube video where an Optimate charger brought back to life several dead or thought to be dead motorcycle lithium ion batteries!!! Looks like they can go into a sleep mode and the internal circuitry wouldn't allow them to recharge.

This is also a problem with cordless drills & cell phones.
If the BMS is blown, NOTHING can get to those cells Frank, go and check it out, compare relevant batteries mate. :)
 
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