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Li-ion from cell phones
#1
Hi all

I got access to a lot this type of batteries (as in several thousand) are they worth something, as part of af powerwall and do anyone know/ got any ideer on how to pack them

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#2
Proprietary batteries can be useful if you have a lot of them. Several thousand is a lot. You could make something up with only these batteries as they are difficult to combine with standard format lithium cells. They usually come with their own BMS, which can be useful. It is just a matter of working out if the BMS works with only positive and negative connections, i.e. no data connections, and checking if the cells still have decent capacity.

If all of that turns out good then you can arrange them in serial and parallel connections matching whatever your requirements are. If the BMS isn't usable you might have to remove it from every battery and need to attach balance connections instead. 3s is a bit odd for usual powerwall systems, you might opt for a 15s system then which can be close enough given the right inverter and so on.
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#3
The best part of having access to several thousand is that you can be picky. You want to get as much of the same model as possible, so if that is the Apple battery in the first picture, see if you can get at least a couple hundred or more of that exact model. Then test them all, and if enough make the cut, build either a 3S, 4S, 7S or 14S pack from them. The reason many people discard prismatics (the type you have) is that there are so many different formats, original capacities, and variations that it is difficult (but not impossible) to make anything useable out of them. If you can get hundreds of the same model, you can at least build a pack out of them. Most of us stick to 18650s and the like because, even though there are many variations and chemistries, they are all one size and mostly come in a relatively small range of original capacities. I agree with DarkRaven that the original BMS's can be useful and might eliminate the need to separately BMS the whole pack! Just check if the BMS works without any sort of data connection (positive and negative work without the other pins needing some input).
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#4
It is dangerous to let the BMS stay when there are more than a few in serial.

critical is the absolute maximum rating of the switching fet involved. Consider one BMS tries to switch off, and the Fet has to take the opening voltage ofe the series in total.
just circumvent the Fet, at least.
The battery contacts are often bad to solder, i saw then crimped.
1 kWp in Test
4 kWh battery target - plus Mobile Home battery
Ultra low cost
Electronics ? No clue. Am machinery engineer.
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#5
I don't think apple batteries have an internal BMS. However, you are going to have your work cut out soldering connectors for them. Probably the best way would be to custom design PCBs for them - both for capacity testing and the final build.
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#6
Thanks for all the replys, sounes like there are a bit of a hassle compared to 18650, so im going to save them for now and work on all the 18650 for now Big Grin
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#7
(03-07-2019, 12:47 AM)Geek Wrote: I don't think apple batteries have an internal BMS. However, you are going to have your work cut out soldering connectors for them. Probably the best way would be to custom design PCBs for them - both for capacity testing and the final build.

With respect, i doubt.
1 kWp in Test
4 kWh battery target - plus Mobile Home battery
Ultra low cost
Electronics ? No clue. Am machinery engineer.
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#8
(03-07-2019, 08:00 AM)Cherry67 Wrote:
(03-07-2019, 12:47 AM)Geek Wrote: I don't think apple batteries have an internal BMS. However, you are going to have your work cut out soldering connectors for them. Probably the best way would be to custom design PCBs for them - both for capacity testing and the final build.

With respect, i doubt.

It all depends how you define internal. In a pack, yes, it will probably be one, but not for each battery in the pack.
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#9
The pack is the battery, in it there are just cells.
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#10
(03-07-2019, 08:00 AM)Cherry67 Wrote:
(03-07-2019, 12:47 AM)Geek Wrote: I don't think apple batteries have an internal BMS. However, you are going to have your work cut out soldering connectors for them. Probably the best way would be to custom design PCBs for them - both for capacity testing and the final build.

With respect, i doubt.

Life is a bitch.

I said the above because i am a lithium addicted.
Or better, not because i am addicted, but by the result it has. I am disassembling each and every unit i can put my hands on, when it is LiIon powered, whether i repair or trash them is irrelevant. I am collecting them from whatever the source is. 
I have had so many different batteries in hand, starting fom the ol' mobiles with their exchangeable batteries, my Ipod (gen 4), Tablets, Smartphones, Household wireless, Power blocks from tools.....whatever i saw had a BMS installed, even if it was so small you saw it only by opening the outer package layer.
(there is one exception, i come to it later). But, theres always reason accepting different opinions and doubts........ always time to learn something new.

Same happened on Thuesday, 3 days ago, i could lay my hands of a few batteries, quickly grabbed together from the trash bin of our garbage collector under the angry eyes of the worker. 2 laptop bats, and a few already dissassemled specimen from unknown source. Only today i had a few minutes to look at them anf found... the following:

 

Apple batts. Wasn't there a thread claiming theres no BMS in Apple's? (Ah, found it Big Grin )

Had not seen them before, i guess a quite new construction:




(Blue) the closing tape on top, where the connection between Stripes of the battery and stripes to the connector are hidden. Very narrow.
(Red) Since the plug is placed on the stripes, it must be a DOUBLE stripe... possiply a bad idea to cut that with pliers ?

Let us look if there is a BMS:



This is the two stripes coming out of the cell. These (usually) cannot be soldered.
And on the other side we see....


(blue) the spot welded connection between the stripes of the battery and that of the Connector Strip.

But - WAIT!

(Red) whats that! Its looking like..... pads on a printed board ?

Unfolding the unit along the lever of the Battery stripes we see :



A very small BMS, leass than 1/10 in wide. The connecting stripe to the connector finally shows as a very thing pronted material as well, so its on two stripes stacked as i thought first.
Unluckily, that it makes de-mounting of these but retaining a solderable point very difficult.

When i came here to write this, i saw that the cells i have seem to be quite similar to the ones the OP has...  given the amount the OP seems to have, a very unlucky situation - but a funny coincidence!!   Rolleyes


Ah - i have to reveal the exceptions where i have seen (pouch)cells with no BMS board (means the BMS function was integrated on the main board): Mostly in Power Banks, when quite big Pouch Cells are used, 8 Ah or something, and when the battery was no click-exchange.

As i said, life is a bitch. Big Grin Big Grin
1 kWp in Test
4 kWh battery target - plus Mobile Home battery
Ultra low cost
Electronics ? No clue. Am machinery engineer.
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