what defines a heater?

Hey guy's,

What defines a heater?

When i was charging some cells, i found that some of those cells where warm to the touch.
I put a mercury thermometer against them and it was reading (pending)between 38 and 42 degrees celsius.
They where charged with the tc4056a with a load that was a constand 900mah-1000mah.
When they where over 3.8v they where getting warm.

The cells in question are the cells in the picture, but it's only those one'sbelow in my hand, the one's at the topdoes not seem to generate so much heat.
This is also a reason for the picture, two same numbers but different looks??!?!?@?
From the same brand but ending on pf(2950ah) did not give so much heat....just like the one at the top.
(charged 250 of them pf's)

Funny thing: ALL of the one's belowin the pictureof my hand seems to have this problem.
Got almost 120 of them. 3 ebike battery's.
They are to old or to abused? Istill don't have an ir meter.

Thanks in advance

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the psu is 30 amp 6 volt, not a aliexpress thingy.
Wire is 60 centimeters long and 4mm thick

Discharge rate and ambient temperature matters in this conversation...

If I saw a 10c delta above ambient at a 1c discharge rate, I would probably throw it in the heater pile.

I would suggest anything over 40C to be a heater. According to most of the spec sheets, they can handle up to around 35C at full charge rate, which can be 2A or more depending on the cell. Laptop cells, that's usually .5C, though.

Granted, the 35C is probably ambient temps, but still. Like Crimp Daddy says, ambient temps matter here as well.

I am curious about that power supply. Its a bloody beast!

Crossposting:

Can we define heater/VAMP/SD
(see Wolfs recent post
https://secondlifestorage.com/t-I-thought-i-was-lucky-when?page=4)

by just defining the capacity lost per hour in mAh (or in % of capacity) ? Could be not so difficult to nail that figure down, and defining what heater/VAMPs/SD are could be much easier on defining a figure to that.

The true definition of a "HEATER" ( at least in the SLS circle) IMHOis a cell that gets to an uncomfortable temperature that is greater thana predetermined temperature either through charging or discharging. Most of us agree that anything over 40C whencharging at the manufactures maximumC rating is a good candidate to be called a "HEATER". If you are on the other hand charging at a low amperage as in 100mA and the cell gets uncomfortably hot >35C That is what I would call by definition a HEATER.Of course, if you're charging them in a45C environment, that won't be a valid observation anymore. so the >10C of ambient temperature rule would be in effect at that point.

When I charge my batteries they do not get even warm especially when i charge them on my 20p board.I cannot notice a temperature difference between the cells. If I get my Thermal Camera out it can see a temperature variance in the tenth of a degree.
Here is what a good set of batteries look like charging at 50mA each




And here are some "HEATERS" (They would be if I charged them at max Current as per manufacturer specs)charging at 50mA each.
Very slight temperature variance but enough to be spotted very clearly by the Thermal Camera.




Wolf

Thermal cameras are such a wonderful tool when dealing with batteries. They provide so much more information and allow you do make better decisions.

Aside from a multimeter, this should be next on the list for tooling up.

It also helps to remove the cell holder from the charging / discharging apparatus. Even though I still use them, I very much dislike the charger/dischargers like the Opus and Lii-500 units. But I get better insight into temps using things like this.

I'd suggest a mercury thermometer would not be a good way to measure temps:
- poor contact with batteries
- slow response
- easy to break (spilled mercury might short cells, v nasty if vapourized)

Maybe use a non-contact type one with a laser guide & some cardboard with a slot ie let the meter see one cell at a time.
Full IR cameras are great but the price, ouch!

Re the heating, a key factor is the current to/from each cell when testing, ie higher current = more heating generally for any cell.
Like said above, "heaters" get much hotter (temp rise vs ambient) than "good" cells in otherwise equal conditions eg the notorious Sanyo red ones.

Redpacket said:

Re the heating, a key factor is the current to/from each cell when testing, ie higher current = more heating generally for any cell.
Like said above, "heaters" get much hotter (temp rise vs ambient) than "good" cells in otherwise equal conditions eg the notorious Sanyo red ones.

Click to expand...

Red, this is the reason why i have made the proposal of defining the heaters/SD Issue with a measurable figure like mAh/per time.

A heater is only a "heater" if the current is high enough.... that is not really a good specification, given how precise all collectors here want to check their goodies.

Wolf, for example, says he has never heaters. But, just recently some of his process detail show that he (obviously) identifies them before they get involved in higher current issues...

Cherry67 said:

Wolf, for example, says he has never heaters. But, just recently some of his process detail show that he (obviously) identifies them before they get involved in higher current issues...

Click to expand...

That statement is "mostly" correct. As I am maturing in my testing strategy and finding out what works, and what does not, several factors have come into play.
It is not that I have never had a "HEATER" I have. It has been a while though as my testing and recovery strategy has evolved. So what have I found out?
High IR and high Amps do not mix well. Take 2 cells of the same manufacturer and part number and 1 cell has 100m? IR and the other one has 50m? IR the 100m? cell will get a lot warmer at the same charging current than the 50m? one. That is a fact.
Most cells that we deal with in laptop batteriesare high capacity and low drain chemistries. I have found that good cells in that categorywill have an IR of ~35m? to 80m? depending on manufacturer and model number. The same goes with high drain batteries their IR tends to be in the 12m? to 30m? range. Any deviation to the higher side of theseIR findings will tend to produce a warmer than normal battery even at a low mA charge. We are talking in tenth of degrees temperatureat that current.
So as I am improving my harvesting strategy yes I do not have any heaters as they never make it that far. I also charge all my cells at the lowest mA possible (300mA for >3V cells and50mA for <3V cells). Does it take more time? Sure but the time I save with my pre charging checks ,IR being the deciding factor, has proven an almost 100% success rate in capacity checks being 80% or above rated capacity and no "HEATERS".

Note: After the initial charge of the cells atlow mA and a successful discharge test. I do charge the cells at generally 500mA and still have not found any heaters. I do a spotcheck with the SKYRC that allows me to charge and discharge the cells at manufactures normalspecifications which can be anywhere from ~0.5C to 2C and still do not have any "HEATERS". The SKYRC is set to turn the cell off if the temp goes over 45C but the highest it ever got during normal testing was 35C on a specific cell. I have pushed experimental cells to the limit and have had it shut down that cell at 45C. Very nice feature as it is cell specific.

More to come on IR you just waite....................

Wolf

Wolf said:

More to come on IR you just waite....................

Wolf

Click to expand...

More! More !!

(Waiting)....


Fight the Haters !

(Thanks for the detailed explanation !!!)

So do we start closing in on a simple definition for heater something like this?:
- starting with a cell in the "normal" voltage range ie between say 3V & 4.1V
- charging or discharging at that cells 0.5C rate (manufacturers spec) causes a temp rise above ambient of 10 degC (or more)
- heater cell might also self discharge
- heater cell likely to have significantly higher IR than manufacturers spec

Redpacket said:

So do we start closing in on a simple definition for heater something like this?:
- starting with a cell in the "normal" voltage range ie between say 3V & 4.1V
- charging or discharging at that cells 0.5C rate (manufacturers spec) causes a temp rise above ambient of 10 degC (or more)
- heater cell might also self discharge
- heater cell likely to have significantly higher IR than manufacturers spec

Click to expand...

Just to fire up the discussion, as i said, heat is only the result of losses, either as SD or in the Inner resistance.

I think about giving a measurement to the losses, like mHh per day or such.

Redpacket Wrote: said:

So do we start closing in on a simple definition for heater something like this?:
- starting with a cell in the "normal" voltage range ie between say 3V & 4.1V
- charging or discharging at that cells 0.5C rate (manufacturers spec) causes a temp rise above ambient of 10 degC (or more)
- heater cell might also self discharge
- heater cell likely to have significantly higher IR than manufacturers spec

I think that is a good start

Click to expand...

Cherry67

Just to fire up the discussion, as i said, heat is only the result of losses, either as SD or in the Inner resistance.

I think about giving a measurement to the losses, like mHh per day or such.

I'm not quite sure on how that would be accomplished. I might set up a 4p charging board with amp meters on those 4 slots and see how these vamp cells/SDs behave. Its going to have to wait a bit though as I have a backlog of projects due to winter weather.
Lots of testing to do for the board.

Click to expand...

In reply to both of you,

Quick Note: Charging and discharging batteries will always create a certain amount of temperature no matter what. It is the degree (amount) of temperature that is in question here. All cells no matter if new or old will have a temperature rise if charged or discharged at high amperage. A high drain battery if discharged at its max rated discharge current will reach 40C to 45C for certain but you are talking serious amperage anywhere from 10 Amps to 30 Amps.
The ambient temperature has to be also taken into account. If you live in a 30C environment then all this needs to be recalculated.

Being the Junior member here to this board ( I have been here for only ~6 months) I have found that there are 5battery classifications.

So IMHO here is something to think about.

InitialVoltage for this scenario is ?3V.

1 GOOD
This battery has an acceptable IR,charges well,testsat least 80% of ratedcapacity,and keeps it charge voltage 4.2Vto within 2% (4.116V)or for some 3% (4.074V) of its charge for at least 30 days.

2 BAD/MARGINAL
This battery has an acceptable tomarginal IR,charges well,but tests to <80% of rated capacity but usually maintains its charge voltage 4.2 to within 3% These cell work great in low capacity requirements and can be recharged and used for other than critical devices.

3SD (Self Dischargers)
This battery has an acceptable IR,charges well,testsat least 80% of capacity,and losesit charge voltage 4.2Vto >4% (4.032V or below) within 30days

4VAMP
Thisbattery has an acceptable IR butcan only be discovered early if charging in a parallelcharging configuration. It will draw the whole pack V down as it passes currentthrough itself,pulling a considerable portion of the amperage through itself but at low amps never shows up as getting warm. When the V stalls on theCC/CVsupply and the amps are still flowing checking all the cells for V will show thatone or 2 cellsare lower than the rest,as VAMP cells. These cells can also be classified as a form of aSD cell.

5HEATER
This battery generally has a marginally high to excessively high IR,is one that warms up to unacceptable levels of C as in >35C or >10C above ambient even with a low amperage charge. Thosecan be almost always totally avoided with an IR check no matter what voltage. Any cell with an IR over 100m? (Except the Sony GR series,don't ask me why yet)is a high candidate and suspect to be a heater.

Addendum
All IR measurement should bedone with a 4 wire Kelvin YR1030 1kHz AC tester or equivalent.
Stay tuned for a comprehensive test on at least four 4 wire Kelvin 1kHz AC IR testers.
Info on IR testinghttps://hiokiusa.com/wp-content/uploads/pdf/18740-UG_WP_BT4560E1-56E.pdf

Wolf

Is it possible you call VAMPS what are "known" as cells stuck on any voltage ?

Cherry67 said:

Is it possible you call VAMPS what are "known" as cells stuck on any voltage ?

Click to expand...

Yes I suppose that could be another way of looking and labeling the VAMP as they do seem to be stuck on a particular voltage and do not like to change
or go above thatvoltage and they want to VAMP the pack down to their level.

Wolf

Thank you all for your replay's.
I had to reread it before i will give an good answer.(and did not have enough time to give a proper/decent replay)

At first the ambient temperature in the shed was between 18-20 degrees celsius.65-68 fahrenheit.

The cells can handle a charge current up to 1450ma.
They where charged with 900 to 1000 ma.
Sorry that "C" story thingy i dont know what value's that are, is somebody willing to explain? thanks.

Crimp daddy wrote:
Discharge rate and ambient temperature matters in this conversation...
If I saw a 10c delta above ambient at a 1c discharge rate, I would probably throw it in the heater pile.

That psu is short: is a Philps psu 30amp 6 v, if you take 40 amps it will lower to 5 volts.
Its also a very good extra heater.
The psu will be more in detail in a next post for the dis/charger tester.

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100kwh-hunter said:

The cells can handle a charge current up to 1450ma.
They where charged with 900 to 1000 ma.
Sorry that "C" story thingy i dont know what value's that are, is somebody willing to explain? thanks.

Click to expand...

C rating = Advertised Capacity / 100.

So if a cell is rated at 2400mAh, then it's C rating is 2400 / 100 = 2.4A
That is why most cells are rated at .5 or even .25 or such C rating for charge. In this example, that'd be 1.2A or 600mA respectfully.

I was holding it like this.
The cells i was calling heaters where getting a lot warmer then all the others that i was pre charging.
For example this lot is not even above 25 celcius, like the rest.
The cells that are below 1 amp max charging, according to manufacture standardswill be seperated charged with 0.5 a
Less then 0.5 max charge....get out.
But can one or two "heaters" affect the temperature of the others?

Yes, btw, i never encountered a heater before, just pre charged ~750 cells

Yes my table is a chaotic mess, i am working on that des/charger tester, you will be surprised when i finished it.
Only designed for soh% with total capacity and ir.
Waiting for my wires to come in.

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Special thanks to Wolf.
Again i will be watching you like a junk yard dog, no i won't bite your.....only keep an close eye on you, i won't even bark.

So you done you're testing on those ir meters and you recommend the YR1030 1kh?

In two three weeks i am also in this ballgame and track/trace every cell by ir soh and the same capacity.

Thanks Korishan, there is some helpful info

Thanks again everyone, big help overhere

Korishan said:

100kwh-hunter said:

The cells can handle a charge current up to 1450ma.
They where charged with 900 to 1000 ma.
Sorry that "C" story thingy i dont know what value's that are, is somebody willing to explain? thanks.

Click to expand...

C rating = Advertised Capacity / 100.

So if a cell is rated at 2400mAh, then it's C rating is 2400 / 100 = 2.4A
That is why most cells are rated at .5 or even .25 or such C rating for charge. In this example, that'd be 1.2A or 600mA respectfully.

Click to expand...

Is that so ?