Edison Batteries

Hi,

Thanks for trying to research this chemistry.

The problem is that Nickle has always been expensive, compared to lead, so even if Edison cells are "better" they are not, in the short term, cheaper.

I'm reminded of our qwerty keyboards that are no longer necessary. Yet very few folks make the switch to dvorak, which would boost average typing speeds by 20%.

Searching_Ut wrote:

I did a search for an hour or so trying to get good performance data on these "Edison" variants and (snip) My gut tells me that as well researched as the technology is being well over 100 years old, the batteries would be widely used by now if the reality could live up to the hype.

thanks for the insight

like i said in my post, i'll stick with my AGMs

MrWizard wrote:
Is that the old chemistry ?

I was under the assumption, there was some new chemistry changes involved in the batteries PT linked too

The training/education I received on Nickel Iron was early 80's. I've been involved in First Article testing to verify contract compliance, and performance/suitability testing of batteries quite a bit over the years for aircraft, and other weapons systems but none of these have been of an "Edison style variety" I've only read some of the data from early military testing on them. NiCad, NiMh, Lead acid variants, and of course Lithium variants I've played with a great deal however in the bench and performance testing arena, not design.

I did a search for an hour or so trying to get good performance data on these "Edison" variants and I didn't really find any data that appeared reliable. It appears these are made by Changhong of China, and that the American reseller advertising doesn't match up very well with the manufactures data and specs. Hard to tell what's going on without a lot of further research. My gut tells me that as well researched as the technology is being well over 100 years old, the batteries would be widely used by now if the reality could live up to the hype.

Is that the old chemistry ?

I was under the assumption, there was some new chemistry changes involved in the batteries PT linked too

It's been about 36 years since the military initially sent me to school on Lithium batteries, and during that training we spent a couple days on Nickle based batteries, with a large part of that Nickle Iron. They've been around a long time, and are well tested. They are useful in some situations, but I can't see them being of much use for an RV. Characteristics that make them a bad choice for RV's would include. Heavy, high ventilation rate of hydrogen gas resulting in needing to be topped off often, very low charge efficiency of only around 60 percent, high self discharge rate, very slow to charge, voltage the drops considerably as SOC drops, and poor ability to sustain even moderately high discharge rates.

Edison cells are not only long-lived, but very tolerant of abuse.

For RV use, besides the size and weight (and these are better than they traditionally were), the main drawbacks I can see are the high charging voltage (which might be too high for some 12V appliances and would at the least be rough on incandescent lights) and the comparatively low charge and discharge rates. Well, the cost here is also a difficulty, but I suspect a good bit of that is due to the differences in scale of manufacture and the "boutique" nature of Edison cells. Nickel is considerably more expensive as a commodity than lead ($4/lb vs $1/lb, very roughly), so unless the commodity markets change dramatically they will likely be somewhat more expensive in any case. (Iron, on the other hand, is very inexpensive comparatively speaking -- a few cents per pound.)

My 675 amp hrs weight 525#, for a 50% DoD of 337.5 amp hrs used
My avg nightly use is 20% aka 135 amp hrs

A set of 30 Edison's cells providing a total of 336 amp hrs,
80% equal 268 amp hrs, 50% equal 168 amp hrs
Might work, but weighs 540# and has total less energy if need arises
And costs a lot more
The only advantage is length of life, does the cost equal this for even the hard core of grid camper
I think a fixed off grid home is the place for these

I would like to see the price of Lth come down so I could reduce the weight and increase the life

pnichols wrote:
Don,

I scratched my head a bit more regarding your capacity vs weight conclusion above.

Note that those Edison Batteries can be discharged to zero/near-zero with no damage. That means that one can use almost the full 112.5 amp hours out of a 12 volt, 140 lb., RV version of them (10 of them in series). As a comparison, my two 12V, 115 amp hour each, AGM RV batteries (for a total of 230 amp hours) weight together about 144 lbs. (72 lbs. each) and I should only use out of them no more than 115 amp hours (one half of their theoretical total capacity) during any single usage cycle.

So, if one can afford them ... those Edison batteries might be a pretty good RV battery bank to buy once in one's RV lifetime and then keep transferring them into each different RV one might own.

The only other concern might be the room that ten(10) of them might take up for each ~112.5 amp hour battery one would want in their rig. I haven't worked out a volume size versus amp hour apples-to-apples analysis to compare against fitting in lead-acid or lithium batteries. HOWEVER if one can find room for them, it looks like the Edisons might last way longer than any equivalent lead-acid or lithium bank of batteries.

Perhaps going back in time can sometimes lead to superior technology. And to think I used to consider air capacitors as the "perfect battery" (ignoring the required size of an equivalent capacitor battery bank). Way to go Edison!!!

they spec 80% DOD on the edisons. Trojan GC are rated for 80% DOD as well. Which I've done hundreds of times on two different sets. The edison do have about a life cycle advantage, but unless your a very very heavy user, it would be hard to run into life cycle issues with a good GC. 500 cycles or more is what Trojan specs for 80% DOD with the std GC. you can go higher with the renewable energy units at a sacrifice of AH.

Don ........ ????????????

1000 cells of WHAT?

Hi Phil,

Yup I got it wrong (again). Mind you 1000 cells would be pretty amazing to have LOL-but then weight WOULD be an issue.