Edison Batteries

pianotuna wrote:
Hi Phil,

Their other advantage is zero plate deterioration, so after 30 years, change out the electrolyte and start over!

The 112.5 amp-hour is 3.2 inches x 5.6 inches x 14.5 inches, weight 14 lbs. (times ten cells).

So for 112.5 amp hours @ 12 volts.

32 inches x 56 inches x 145 inches. A huge space issue. When I first read it--I thought each cell was 140 lbs.

No, for 10 cells you only multiply one dimension by 10, which ever way you are lining them up, or one by 2 and one by 5 if stacking. 10 cells would fit in 16 x 11.2 x 14.5 Multiplying each by 10 gives you the space needed for 1000 cells!

Hi Phil,

Their other advantage is zero plate deterioration, so after 30 years, change out the electrolyte and start over!

The 112.5 amp-hour is 3.2 inches x 5.6 inches x 14.5 inches, weight 14 lbs. (times ten cells).

So for 112.5 amp hours @ 12 volts.

32 inches x 56 inches x 145 inches. A huge space issue. When I first read it--I thought each cell was 140 lbs.

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 @ 14 lbs. each). 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!!!

Thanks Phil for having a look to find more info. It is too bad they are so low on capacity vs weight. Looks to me as if a stationary battery bank would be great given their ability to be flattened. That makes them better than LI--plus I doing thing there is an issue with cold.

Don,

I followed one of your Edison (nickel-iron) battery links. Thanks for the links.

Here's my comments after a quick read:

- A 112.5 amp hour 12 volt configuration requires ten(10) 1.2 volt Edison batteries in series for an RV ... very heavy at 140 total lbs. for "one battery". HOWEVER, it looks like you would only need one 112.5 amp hour configuration to get close to a usable 112.5 amp hours of capacity, since they can be almost completely discharged each cycle with no damage.

- The above configuration would also be physically large for an RV ... at 3.2 inches by 5.6 inches by 14.5 inches for EACH of the ten(10) cells.

- An Edison battery would last the life of one or more RVs.

- I don't understand the electrolyte being used. Would it corrode battery compartments, connectors, and the clothes you're wearing just like with LA batteries?

- The recharge voltage looks high ... 16.5 volts for ten(10) cells in series (1.65 volts per cell). What's the downside to battery life if one is willing to take a longer time to recharge by using a lower charging voltage?

Here's more detail from the first link you provided:

http://ironedison.com/images/Spec%20Sheets/1.%20Nickel%20Iron/Nickel%20Iron%20Edison%20Data%20Sheet.pdf

People do have real world experience with Nickel Iron Batteries. I personally know a friend running a large set for his Ham radio station at home. A smaller set that used to be in his TC till it was sold and he has not installed them in his class A as they would be in the nose and doesn't want to add all that weight up there. Best places to get info about them, that I have found, is on off grid solar forum boards. I personally would not use them in a mobile environment as they are very heavy and have different charging requirements than FLA battery. Seems that FLA is still the most bang for the buck. For the money it would cost for new ones, I could buy LOTS of FLA.

MrWizard wrote:
Some body brought this up a little while back

IIRC. Nobody had any real world experience with them

COST :E being the reason ;) ... even AGMs are considered "pricey" by many, ergo the reason good ol' flooded batteries will still be around for quite some time yet, despite the advantage these newer technologies may offer.

Some body brought this up a little while back

IIRC. Nobody had any real world experience with them