Large Scale Central

Safety Check for Old Batteries?

Electronics
#1

One of the members of the local rocketry community recently gave away rechargeable batteries to all takers rather than pay to ship them. I took the following:

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Beyond the voltages, I have little more information than “Lithium-ion.” Some of the batteries are self-balancing, apparently. I did a cursory inspection of the homemade packs on the upper part of the photo. There are some wires that have pulled away from the circuit boards, but there is no apparent damage to the batteries. I should note I also got a charger to go with this stuff.

Is there some way to test this stuff beyond charge them, plug them in, and see what happens? If I do that, should I keep the charger under direct observation?

There is the potential for more than a few battery cars in this…if they are safe!

Thanks!

Eric

#2

A high quality charger should tell you if there is something amiss and will not charge until you read the screen and hit the “start” button.
My charger has done that a couple of times for me.
This is what I use:

#3

NO. You should buy a charging bag for Li batteries! They have been known to burst in to flames. [I confess that I didn’t have one until recently, but I was working with small packs of new batteries.]
Like this:
https://www.amazon.com/Zeee-Battery-Fireproof-Explosionproof-Capacity/dp/B07KZQZBN2/ref=sr_1_5

LiIon batteries are NOT self-balancing. They may include a Battery Management System board (BMS) which will control over-charging, under-voltage discharge, etc. I use these amongst others:
https://www.aliexpress.us/item/3256805624313715.html
Scroll down to “Product Specifications” and take a look at all the parameters they manage.

#4

You can’t ship them by air over on the mainland - from Hawaii you possibly have to send them by sea?

“Balancing” is feature of some chargers, and requires that wires from each battery are connected to the charger, so it can monitor what is happening with each one. The r/c car guys care, but we train guys don’t, so our battery packs should have a BMS and only a pair of wires.

DO NOT let them short circuit - they can produce huge currents for a short time, and will burst in to flames. I suggest you unpack that box and put them, safely wrapped, in something that won’t let them be a problem. A plastic craft box?

Before you proceed, maybe take some photos of the PC Board on the top batteries, and the charger, and those packs labelled 24V, so we can advise further?

#5

I put mine into a galvanized metal bucket for charging. Just in case there is a problem, cheap insurance. And get a good smart charger, as above.
Jerry

#6

Nice haul, Eric!

Speaking of safety, if there are any batteries with exposed ends, it would be a good idea to put electrical tape over them.

I’m no expert on this, but I recall a safety video where a guy’s house burned down, and the source was a bucket of used batteries he’d been accumulating for “recycling.” The exposed terminals somehow connected in a bad way.

This is especially the case with Lithium-Ion batteries, which are notorious for causing fires.

Sorry if I’m sounding preachy…
Cliff

#7

I can’t take it any longer!

Mean while at Eric’s house!!

#8

Ok. Thanks everyone. There is a lot to digest here. I will get after the details and post them. In the meantime, I will make sure the are safely stored.

Eric

#9

Update:

I did a visual inspection and a bit of search engine work.

I first looked at the bundles marked 24V and 12V. They all had the following label:

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The difference seemed to be how they were wired, with the 12V bundles having more wires coming out of them than the 24V bundles.

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My assumption here is that the 24V bundles are two “packs” of batteries wired in series; the 12V bundles are identical “packs” wired in parallel.

I then took a look at the little grey batteries. These seem to come together in two-battery “packs,” with each battery wired in parallel using a common bus across each pole.

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Internet bummeln indicated that the top number, which was common across all batteries, was a battery type, making these lithium-ion. I am assuming the lower number is a batch or serial number.

These batteries come in their two packs as shown, in the following series connection…

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…and in this configuration with some sort of circuit board. You’ll note that the red and white wires are cut near the pigtail connector .(Navy term for the ship-to-shore power connector)

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I have two chargers, the charger I got with these batteries, a EOS0610i Duo, and the one I got when we tried to breathe life into our B’mann railtruck, an IMAX B6AC. Note that I do not have the correct pigtails ready-to-hand to use this more modern charger.

For the moment, all the batteries are laid on in the shade on our lanai with their terminals well separated. I have to read some of the manuals and order a charging bag before proceeding.

Thanks again for all the tips and warnings!

Eric

#10

Probably…At any rate, shipping costs as much or more than the batteries, which is why we invested in railclamps rather than batteries. Railclamps proved the most economical way to run a variety of trains. Our LGB sound car and B’mann tenders have shown that sound systems are fun…for five minutes…on our little railroad!

Eric

#11

Quite a lot to digest here!

First note: the black foam is just padding added by the owner. If it isn’t glued on, I suggest you try to take it off, without destroying any wiring.

A quick search showed they are medical equipment batteries. The 12V is actually (maybe) a 3S2P 11.1V lithium. [3S2P = 3 cells in series, 3 more series cells in parallel. Doubling them up like that gives you longer run times.]

That’s a reasonable assumption. As the basic building block is the 3S2P 11.1V pack, then they could be wired as you describe. So the 12V are 3S4P and the 24V are 6S2P.

And you can clearly see they have NO ‘battery management system’. Nor do the big Masimo packs - the BMS electronics are inside the medical device they plug in to.

That is NOT a BMS board (imho) A closeup view shows no signs of wires going to the individual batteries.

As far as I can see, those are completely unprotected battery packs. A quick scan of the charger specs (nice device, btw,) suggests that it monitors battery voltage as it charges, so maybe someone thinks a BMS isn’t necessary.
It is - when you USE the batteries, they will discharge and you need to cut them off before they hurt themselves.

It might be that, whatever they were used in, had the battery protection features built-in.

#12

Eric, a quick primer on Lithium batteries - we had this conversation with Devon:
https://largescalecentral.com/t/charger-for-14-8v-lithium-ion/81665/9

1 Like
#13

That white stuff worries me. If you can’t prove it is glue, then dispose of them (in the “hazardous waste” dump.)

#14

@PeterT ,

Thanks again for the thorough response. I have to get my head around all of it, but, in short, to get one of these battery packs to work, I would need:

  1. The battery charging bag.
  2. The battery management system board.
  3. A means to connect the battery to the charger.
  4. A means to power the EOS0610i Duo, should I choose to use that charger.
  5. The usual battery harness for train use (I am assuming these are no-go for charging in any future battery car).

I am beginning to wonder about this windfall…Lots to chew on here.

Eric

#15

Well, the first issue is that they are 11.1V packs. You can’t easily make them 14V or 18V.

We usually use 4S1P or 4S2P packs, which are 14.4V and just about good for Bachmann trains. A 5S2P pack would be 18V and good for the USAT multiple units, etc.

The next issue is that they are already soldered or welded together. The Battery Management System board requires that you connect a wire to each battery end.

I charge mine in situ - in fact, I just charged my 2-6-0 tender yesterday on my workbench. I should have put it in the bag that I got for Xmas.
Short answer, buy a bag big enough for the battery car!

This pack might be a good place to learn, as you can cut the wires between the batteries.

If it were mine, I would reduce it to a 4-battery pack by cutting the black wire at the top to separate 2 of the batteries. (I assume there are wires at the bottom too?)
Then I’d get one of these 4S BMS units and wire it up as shown. As your pack already has wires, it will be easy to reach them and add new ones.

image
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#16

The other Masimo packs are apparently 3 batteries in series, plus another 3 in parallel. Why don’t you remove the padding and the shrink-wrap cover and post a few more photos?

#17

I agree …sure looks like leakage but it could be a miniature spider nest?

#18

@PeterT and @Rooster :

OK, many more thanks. I will investigate further this weekend if not sooner.

Eric

#19

There was a typo in my post, now corrected. “reduce it to a 4-battery pack” .

A little more background - I think it is fair to say we (the battery-r/c crowd) run Bachmann and LGB locos on 4 Lithium Ion cells. While LGB locos will take more, tat just means they run faster. I can’t imagine you need that!

#20

I may have missed this, but have you measured the voltage on any of the batteries and packs? Are they still good? Even Li batteries die, and if they are compromised, all the effort to integrate them with your trains will be wasted.
Just a thought

Jerry