identification request - old crated NCads

[tandrews]

These batteries were acquired with a vintage tower and wind gen system.
I can't find any way to identify them, capacity, charge rates, or any useful detail from packaging or cell data. They had been stored in a barn for years and only a few banks had a hint of voltage remaining. I know they may be garbage, but also need to know how to verify.

I welcome input from anyone who has seen similar cells/crates and /or pointers to further info.

Pics:
Old NiCads

Thanks to those who can offer some useful info.

[Sunking]

I can tell you the voltage of each cell is 1.2 volts as that is what all NiCad cells are, and judging from the physical size around 200 AH.

[tandrews]

Thanks, that jives with my research so far, although I welcome citation to enforce the suggested voltage in the older cells pictured. The white and translucent casings are mostly surely 1.2vs - the larger (sorry I really didn't included scale here) are the ones in question as they are at least 15 years old. Larger cells are approx 2"x6"x 12". As strings of eight, these are more likely 1.5v nominal.

I am concerned about carbonation due to this vintage, but uncertain how to test for it, or if technology has improved that I may have some method to de-carbonate like desulphation in lead acids.

I understand procedure would be to equalize (short individual) cells overnight then charge and top up electrolyte with distilled. Suggestions welcome on the drawn out process to charge and test individual cells to avoid reverse charging a stringed cell and weed out the bad ones from the cases.

I have a DR2412 which can be set to charge modified strings of Ni Cads, but no battery sensor to avoid overcharge and thermal runaway. Hints and tips are welcomed.
I look forward to determining what capacity remains in these vintage cells.

Ref:

http://en.wikipedia.org/wiki/Nickel-cadmium_battery_vented_cell_type

[Sunking]

Thanks, that jives with my research so far, although I welcome citation to enforce the suggested voltage in the older cells pictured. The white and translucent casings are mostly surely 1.2vs - the larger (sorry I really didn't included scale here) are the ones in question as they are at least 15 years old. Larger cells are approx 2"x6"x 12". As strings of eight, these are more likely 1.5v nominal.

Ok you got me scratching my head. Are they Ni Cad? Ni Cad nominal voltage is 1.2 volts, alkaline cells are 1.5 volts.

I am concerned about carbonation due to this vintage, but uncertain how to test for it, or if technology has improved that I may have some method to de-carbonate like desulphation in lead acids.

I understand procedure would be to equalize (short individual) cells overnight then charge and top up electrolyte with distilled. Suggestions welcome on the drawn out process to charge and test individual cells to avoid reverse charging a stringed cell and weed out the bad ones from the cases.

I have a DR2412 which can be set to charge modified strings of Ni Cads, but no battery sensor to avoid overcharge and thermal runaway. Hints and tips are welcomed.
I look forward to determining what capacity remains in these vintage cells.

Ref:
http://en.wikipedia.org/wiki/Nickel-...nted_cell_type

Ok you are still confusing me. Are we talking Ni Cad or Lead Acid? Ni Cad and Nickel Halide have very peculiar charging algorithms that do not lend themselves very well to Solar and Wind applications, great for power tools and EV's, but very challenging for solar and wind.

[tandrews]

I'm asking, and judiciously applying caution to what I read until I know.
While I appreciate that *most* NiCads cells are 1.2v, I'm not ready to accept that these are 1.2v given they have not yet been identified. You can tell me they are, but neither of us know for sure. I am hoping someone with experience with these cells will see my post and help expose some data on specs.

A string of 8 cells @ 1.2 yields 9.6v which does not neatly fit a 12v setup.
Before you ask how they were configured, what sort of system they were hooked up to, or other historical request, I will tell you I don't know. This is the reason I ask for identification.

I know NiCads are not considered the best platform for PV or wind, but I have a bunch of them and they may or may not make up some storage eventually. One step at a time.

[tandrews]

Bump on thread to get it seen again.

[tandrews]

bump2 - anyone?

[Mike90250]

the chemical process in ni-cad only allows for 1.2 v unless they are overcharged somehow, or fresh off a charger. There is no 1.5V variant of ni-cad. If you get 1.5V, you have something else.

[tandrews]

I realize those reading this with a lead acid mindset may be confused or distracted from my request. These are vented nicads, but I wish to identify them.

ref: http://en.wikipedia.org/wiki/Nickel-...nted_cell_type

They were acquired with a wind system, which may be 24v, thus explaining the string configuration of eight cells per crate.

Based on the lack of response to the question posed, I suspect I may be on my own to sort identification and managing this array.

[SteveC]

This is interesting, and I wish I could be of assistance. But I don't know anything about them. I have a buddy who knows a lot more than I do [and I only know about lead-acid I've been using for 30 yr.] but he's out of the country a while and when he returns I'll ask him if he knows any sources you could tap for info'.

Meanwhile, good luck. There has to be a way you can find out what you need and want to know...I'll continue to ponder it.

[tandrews]

Given the vintage of these cells, I have not yet determined if they are in fact Nicads.
They may well be NiFe or NiZ Alkalines for all I know.
Certainly the metal containment for the larger cells leans that way.

In fact (this just in!) this thread:

http://fieldlines.com/board/index.php?topic=143544.18

pretty much answers the question.

These are indeed NiFe batteries.

http://bellsouthpwp.net/j/o/johngd/files/misc/Edison%20battery.jpg

At least now I know how to direct my research and now everyone reading this has a bit more knowledge.

[Sunking]

OK if they are NiFe they are 1.2 volts per cell.

[tandrews]

lol, thanks.

More specifically, and due to my recent liberation from ignorance:

The proper float voltage is 1.45 volts per cell. If 10 cells were used, the proper charge voltage would be 14.5 volts.

The charge voltage can vary from 1.46 to 1.55 volts per cell. Unlike other battery designs, the exact charge voltage is unimportant. A higher voltage will result in quicker charges but more water loss that will necessitate more frequent topping up with distilled water. Since the cells can withstand overcharge there is debate over what constitutes a proper charge voltage. The higher you go the quicker water will disappear from the batteries. At voltages greater than 1.5 volts/cell the batteries will store approximately 15% more power than they are rated for. If 10 cells were used, the charge voltage could range from 14.6 volts to 15.5 volts. It is probably better to use the 1.46 volts / cell level of charge in order to minimize water loss if the battery will be unattended for months at a time. Regenerative catalytic caps are available to combine the h2 and o2 back into water if unattended maintenance is required. There are also auto watering systems that are available.

The proper equalization voltage is 1.65 volts per cell. If 10 cells were used, the proper equalization voltage would be 16.5 volts. This equalization charge is applied for 8 hours using at least C/10 current. According to Edison's original manual from 1914, it is best to completely discharge the batteries from time to time before applying the equalization charge. Edison also recommends a 1.7 volt equalization charge and he recommends changing the electrolyte every 5-10 years.

ref: http://www.nickel-iron-battery.com/

next reasonable question: where might one source replacement electrolyte?

[Sunking]

lol, thanks.

More specifically, and due to my recent liberation from ignorance:

The proper float voltage is 1.45 volts per cell. If 10 cells were used, the proper charge voltage would be 14.5 volts.

Do a little more research on Nickel batteries. You are correct float voltage is 1.4 volts to keep up with the rapid self discharge of NiFe, but when the sun sets or the charger cannot keep up the nominal voltage is 1.2 volts like any Nickel chemistry battery. Does not matter if it is NiCd, NiMh, or NiFe as it is Nickel.

[tandrews]

Research has only just begun as is evident from my post.
My last question remains unanswered however.

While NiFes may last forever, and mine may in fact be just as functional as when they were stored so many years ago (SCORE!). I do expect that there will be a number of cells which will need new electrolyte to begin new life.

Any references you can offer are welcome, as they add value to the thread and forum.