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  • Thought I'd drop in an update for posterity. I did a couple dozen tests over the holidays with the nickel irons I have. I'll post raw data if anyone cares to see it, but here's a quick summary of what it says to me...

    My test bank is made up of Edison C6 sells. My cells are between 50 and 60 years old and had not been reconditioned at the point when I got them. Using my reconditioning process without opening the cells, I got them up to about 300 amp-hr when overstuffed with "juice". The only reference I can find on these cells are that they are said to have an original capacity of 337.5 amp-hr (but that a single source with no Edison reference). So I'm about as good as I can expect for what I've done to revive them.

    The coulombic efficiency of the cells on charge / discharge was very surprizing high when only using the bottom half of the batteries' amp-hr of storage - 90%+ efficient (perhaps 95% or even more at low amp draws). Since this was from scores of tests, I deem it to be real. This efficiency is much higher than anything I have seen reported before and suggests the batteries indeed might be quite useful for solar applications if you operate in these ranges, but it means you need even more cells (and $$ to invest). NOTE: As one should also suspect, the water consumption by the cells is also dramatically reduced when operating within this improved coulombic efficiency range.

    There are two major "watch outs" that these experiments point out....

    (1) The discharge-charge efficiency takes a major nose dive as you continue to pack the cells. The more you try to store, the worse the incremental efficiency gets. This makes it very wasteful to attempt to utilize all of the stated capacity. While this might be fine for on-line backup power devices, efficiencies of 30% and less are most assuredly way too low for most of us attempting to store electricity being generated from from solar panels. NOTE: I should emphasize, I only know the coulombic efficiency break point for the cells in my possesion. That same point of diminishing returns for other cells would have to be independantly determine, and it would be unfair to generalize that other cells should also only be used to 50% of stated capacity.

    (2) Coulombic efficiency is NOT total efficiency - ie even if amp-hr out is equal to amp-hr in (100% efficient), you still have to take into account the volts necessary to charge the cell versus the natural volts the cell runs at during discharge. WHile there is no one specific set of values I can give you because charge rate comes into play, typically my charge source was at about 1.6v when the cells were at their 50% capacity level (150 amp-hr). Using 1.2v as the average discharge volts, that gives us a "real" wattage efficiency of about 75% as the best we can expect to achieve (compare that to 90% for LA cells using the same type of analysis).

    Finally, after reviewing all these experiments I'll expand my initial generalization to Mike and sugest there is about 15-20% power remaining at the 1.1v level as you continue the discharge to 1.0v.

    Comment


    • Originally posted by Robert1234 View Post

      I should have looked more closely at the title of this thread "Nickel Iron vs. Lead Acid - Off Grid battery debate". The DEBATE word should have cued me in that firm opinions had already been set. Going forward, I'll try to limit my discussions on this board to more non controversial subjects such as array configurations, charge controller settings, etc. For the record, I'd like to leave this thread with one last thought as it has served me well over the years in my career:

      "It is a good morning exercise for a research scientist to discard a pet hypothesis every day before breakfast." - credit Konrad Lorenz - 1973 Nobel Peace Prize recipient.
      Don't quit now, we are finally getting into decent research and asking serious questions about this technology!!

      Comment


      • Originally posted by Robert1234 View Post
        Thought I'd drop in an update for posterity. I did a couple dozen tests over the holidays with the nickel irons I have. I'll post raw data if anyone cares to see it, but here's a quick summary of what it says to me...

        My test bank is made up of Edison C6 sells. My cells are between 50 and 60 years old and had not been reconditioned at the point when I got them. Using my reconditioning process without opening the cells, I got them up to about 300 amp-hr when overstuffed with "juice". The only reference I can find on these cells are that they are said to have an original capacity of 337.5 amp-hr (but that a single source with no Edison reference). So I'm about as good as I can expect for what I've done to revive them.

        The coulombic efficiency of the cells on charge / discharge was very surprizing high when only using the bottom half of the batteries' amp-hr of storage - 90%+ efficient (perhaps 95% or even more at low amp draws). Since this was from scores of tests, I deem it to be real. This efficiency is much higher than anything I have seen reported before and suggests the batteries indeed might be quite useful for solar applications if you operate in these ranges, but it means you need even more cells (and $$ to invest). NOTE: As one should also suspect, the water consumption by the cells is also dramatically reduced when operating within this improved coulombic efficiency range.

        There are two major "watch outs" that these experiments point out....

        (1) The discharge-charge efficiency takes a major nose dive as you continue to pack the cells. The more you try to store, the worse the incremental efficiency gets. This makes it very wasteful to attempt to utilize all of the stated capacity. While this might be fine for on-line backup power devices, efficiencies of 30% and less are most assuredly way too low for most of us attempting to store electricity being generated from from solar panels. NOTE: I should emphasize, I only know the coulombic efficiency break point for the cells in my possesion. That same point of diminishing returns for other cells would have to be independantly determine, and it would be unfair to generalize that other cells should also only be used to 50% of stated capacity.

        (2) Coulombic efficiency is NOT total efficiency - ie even if amp-hr out is equal to amp-hr in (100% efficient), you still have to take into account the volts necessary to charge the cell versus the natural volts the cell runs at during discharge. WHile there is no one specific set of values I can give you because charge rate comes into play, typically my charge source was at about 1.6v when the cells were at their 50% capacity level (150 amp-hr). Using 1.2v as the average discharge volts, that gives us a "real" wattage efficiency of about 75% as the best we can expect to achieve (compare that to 90% for LA cells using the same type of analysis).

        Finally, after reviewing all these experiments I'll expand my initial generalization to Mike and sugest there is about 15-20% power remaining at the 1.1v level as you continue the discharge to 1.0v.
        Robert,

        I have some original Edison documents in a 3 ring binder. It states C6 cells are 338 AH, with a normal charge rate of 67.5 amps. The list price per cell was $62.90 each from a sheet dated July 12, 1948.
        I have 18 C6 cells with serial #'s around 3336KK, not sure how old they are. I did test one a little over a year ago and have been using it with some other NIFE types to power my garage and landscape lighting.
        I don't think I am getting the capacity on the C6's you are, but some of my other Edison types are near 100% of new performance as shown on Edison sales brochures. Test data for a cell below.

        Battery Model Battery Serial Number Date Log I.D. Load Amps Start Volts End Volts Time Notes Decimal Time Calculated Amp Hours @ 1.3V

        C6 3336KK 10 25 11 C6 3336KK 5AD1 5 1.4 1.1 29:47 00 End charge 1.654V 7.6A
        C6 3336KK 10 23 11 C6 3336KK 10AD1 10 1.45 1.1 13:20:10 13.336 133.36
        C6 3336KK 10 22 11 C6 3336KK 15AD5 15 1.4 1.1 10:32:50 10.547 158.21
        C6 3336KK 10 17 11 C6 3336KK 20AD1 20 1.35 1.1 8:25:10 8.419 168.38
        C6 3336KK 10 20 11 C6 3336KK 20AD2 20 1.35 1.1 8:12:20 8.205 164.11
        C6 3336KK 10 15 11 C6 3336KK 60AD1 60 1.25 1.1 2:56:00 2.933 175.98
        C6 3336KK 12 24 11 C6 3336KK 60AD2 60 1.3 1.1 2:30:10 End charge 1.650V

        Comment


        • The data I have (again not official Edison documents) says KK series cells are from 1941. Like you, my NiFe's are performing non-critical duty right now as I need a whole lot more to put them into main service.

          I have answered the questions I originally had, and now it all comes down to sourcing and availability of the cells for me now on the decision to go NiFe or LA at the cabin. Based on the data I have I am looking to get 100 more C6 cells to add to my existing 20 so that I can run 3 parallel banks of nominal 48v. That will give me about 22 kWh of high efficiency storage with a peak capacity of about 45 kWh. Unfortunately, my source has sold all he had so I am on the lookout for more. Might have a line on some C8's but that is yet to be confirmed.

          Bottom line, I want to go NiFe, but unless I can find more cells at my previous investment, it's gonna have to be LA.

          Comment


          • How are you guys sourcing your used batteries? Ebay, Craigslist? I would love to find some to mess around with.

            Comment


            • edison Battery Source

              Originally posted by Saggys View Post
              How are you guys sourcing your used batteries? Ebay, Craigslist? I would love to find some to mess around with.
              I've had mine since the mid 1970's and never used them until recently. I purchased the set I am using now from a rancher in Nebraska. The rest came from Pullman cars being restored by a railroad historical society. Ebay does have them once in a while. There are usually only 1-4 cells which are not good for much. There was a place in New York that was selling larger sets on eBay for a while. I will dig around and try to find their address.

              Comment


              • The "place in New York" was probably my source, but he has no more. Zappworks bought them all.

                Comment


                • Thanks

                  I'd like to thank everyone who participated in this discussion, especially Old Bill with his funny bashing style and Robert1234 for the scientific approach. 21 long pages, but a very interesting read.

                  I'm very much a novice when it comes to everything electric, but willing to learn as I'm planning to install this year or next year what I believe in English is called a grid-tie with power backup system. I want to use most of the electricity that the 5 kWp system generates, and thus a 5-7 kWh battery system might be interesting. There are certain aspects of the NiFe battery that appeal to me, such as the environmental aspect and longevity. I'm not so enthusiastic about changing electrolyte, especially if it's every 2-3 years. But this depends on the quality.

                  In this respect I have one question: the discussion has been about old Edison batteries and modern Chinese versions, but how about the Russians? Are they doing anything differently?

                  Comment


                  • Originally posted by Neven View Post
                    I'd like to thank everyone who participated in this discussion, especially Old Bill with his funny bashing style and Robert1234 for the scientific approach. 21 long pages, but a very interesting read.
                    Hi Neven - Welcome to Solar Panel Talk!

                    Russ
                    [SIGPIC][/SIGPIC]

                    Comment


                    • Hello Nevin, I'd like to welcome you as well and thank you for the kind words.

                      Unfortunately with regards to your question, I have no personal experience / data with any NiFe batteries other than the Edison cells that I can share - although as always, I do have my opinions .

                      I believe a lot of the general knowledge / techniques obtained via work on the Edison cells should translate over well to most all NiFe technologies. I have my "baby bank" of cells running day in and day out now at well over 90%+ coulombic efficiency consistently and have decreased my water consumption dramatically (watering looks to be needed maybe every 2 months or so - and that's with the small headspace that the C6 Edisons have in them). Basically, I think the cause of most all the issues brought out in this discussion is that we've all been trying to store too much energy in the cells because we're told they can take it. Back off the juice and the power inefficiencies, hydrolysis, misting issues, iron poisoning, etc all get minimized. (Unfortunately that means MORE cells and MORE $$.)

                      With all that said, I personally can't justify investing my resources (read that as $$) into the NiFe cells being marketed today because of the high prices. I only paid about $34 each for my cells. While that's still a 2x premium over a LA forklife battery based on $/kWh the way I suggest using them, it's a far cry from the 10x premium that the market is charging for new cells. I continue to look for used cells to add to my NiFe supply, but unless I find a lot more of them, I will be utilizing LA forklift packs for my main power storage needs at the cabin.

                      Hope this info helps.

                      Comment


                      • Thanks for the welcome

                        The reason I ask about the Russians is that I live real close (in Austria) to a guy who sells Russian 300 Ah NiFe batteries for around $600/kWh. He maintains longevity is 20-100 years, depending on how you threat them, that the batteries don't mind being overcharged or completely depleted (after reading several forums I don't think that holds up), and that if you change the electrolyte every 10-15 years and do what the manufacturer advises, the batteries might well outlive you.

                        Like I said, I like the idea of only having to buy batteries once, especially batteries that contain a minimum of crap (unlike lead acid batteries), but "MORE cells and MORE $$" (because it's best to charge and discharge them in the 50-80% range, if I remember correctly) and changing that electrolyte make me a bit hesitant. And when I look at state-of-the-art LiFeYPo4 batteries that are so small... Who knows what else is out there! I'm just beginning to scratch the surface here.

                        But anyway, I'm going over to the guy selling the NiFe batteries next week. See what he says. Should be interesting.

                        If anyone has any info on Russian NiFe batteries I'm all ears though. Buffalo Bill Blake, the charlatan hunter, said he didn't say anything about the Russians because he didn't know what they did wrt NiFe. That's just about everything I read about the Russians here and elsewhere. But I've been reading for just 20 hrs so far.

                        Comment


                        • Neven ... Your going after the 'Smart Slice' of dat Ni-Fe pie.

                          That 'sweet' 50% to 80% slot is exactly where the Ni-Fe Cells seem to compete well.
                          Of coarse anyone that would read what the Chinese were actually saying has known
                          that for a good while now.

                          Also the sly devils didn't STOP that Charging / Water Usage Chart at 1.6 Volts Per Cell
                          by accident. Nice to hear that you picked up on dat one as well.


                          For a well funded Survivalist type that can Properly store a lot of chemicals it can be A WAY to go.
                          IF the day ever came that you just couldn't buy new Cells - for whatever reason -
                          than all new rules run the battery show.


                          I had the Russian Ni-Fe Cells back in the 70's but never paid enough attention to them
                          to be able to say much today. They were about the same size as my 'main man',

                          The Russian's sent me some info in 2012. They said that they would like to push products
                          in America but were never able to make it happen - the devils

                          I looked real 'good and plenty' but did not see where they have anything like what
                          Changhong and The Electric Indian has available for the greedy American


                          Old Bill Blake

                          [B]Mod note - Old Bill - Leave off the name calling and blather - make your case with facts only.[/B]
                          Last edited by russ; 02-15-2013, 11:44 PM. Reason: removed blather and attack

                          Comment


                          • For a well funded Survivalist type that can Properly store a lot of chemicals it can be A WAY to go.
                            I'm not well-funded, not a survivalist and I can't properly store a lot of chemicals. So that's a tad problematic.

                            If I can only use 30% of the battery's capacity, I'd have to buy at least 15 kWh worth of NiFe batteries to get the 5 kWh I'd probably need for my setup. 15 x $600 = $9000 (EUR 7500). I can't afford that, I think. It'd be an option if I'd have the guarantee that the batteries will function for over 30 years...

                            Complicated stuff, difficult to find good info on environmental aspects of batteries of different plumage. I think I might wait, and buy and build an array in 2014.

                            I'll report on what I find out about the Russian NiFe batteries.

                            Comment


                            • Neven, You can use any percentage of the Ni-Fe cells that you want - however it
                              does sound like you can get into some real stupid percentages as far as water consumption
                              and charging efficiencies go.

                              POOR charging efficiency Top AND Bottom according to Changhong.

                              That fact seems to have gotten Lost by people sinking a lot of money into Ni-Fe -
                              It no Lie.

                              According to Changhong if you run their Ni-Fe Cells down too much 'certain' Lead Acid Cells put
                              a severe stomping on them as far as Longevity goes.

                              They do shine (Life Cycles) if they are treated about the same as typical Lead Acid cells.
                              Just spare them the myths and wives tales and read the Manufacturers Charts.

                              The big question is since they do not sulfate can we avoid that difficult ... LAST 20% between
                              80% to 100% ?

                              Yes the holding Capacity will drop but will the Net Capacity still be enough.

                              How often would they need a good BOOST CHARGE ?

                              About the same as what they recommend as a 'Finish Charge' regimen for Lead Acid batteries -
                              old Bill will guess.

                              Yet another 'First' here at SPT.

                              I'm not trying to make "a case" since there is no money in this game for me. Zero.
                              I am involved with research in a business that has plenty in it - but not here.

                              Someday I would like to see people have 'The Submarine Type' Ni-Fe Battery again which was the
                              real crowning achievement of Mr. Edison and his gang.
                              I wrote about it in the Fieldlines OtherPower Forum last year.

                              The Easy to Drain - easy to Refill - easy to refurbish (over and over) 'Sub Type Ni-Fe'
                              came AFTER they wrapped up many years messing around
                              with the conventional Ni-Fe battery.

                              Tens of Thousands of Man Hours and Hundreds of Millions (in todays money)
                              went into the Ni-Fe ... WAR BATTERY.
                              WWI that is.

                              This thread now has over 30,000 views.

                              By 50,000 views we will have it all figured out .. in spite of things.


                              Bill Blake

                              Comment


                              • Old Bill - Easy to preach to the unknowing isn't it - not even any knowledge necessary possibly?
                                [SIGPIC][/SIGPIC]

                                Comment

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