We are unloading containers full of batteries every 90-120 days.  

Coming January 2014:  300Ah cells (12V, 24V and 48V available)

Coming March 2014:  500Ah cells,  800Ah cells  (12V, 24V and 48V available)

Reserve your batteries today, they always sell out before they arrive in our warehouse!!!                                                        Thailand and SE Asia Please call today at +66 83 647 3443 danieldonatelli@hotmail.com 

The Last Battery You Will Ever Buy

Iron Edison recommends Nickel Iron (Ni-Fe) battery technology for your off-grid or renewable energy storage needs. Vastly out-lasting the 7 year life cycle of their lead-acid counterparts, Nickel-iron battery systems have an expected life of twenty five years or more and are quickly becoming the environmentally sensitive choice for off-grid and renewable energy storage applications.

Over a century ago, Thomas Edison found a battery design that he considered to be nearly perfect. Today, Iron Edison is proud to offer an updated version of this incredible design that is specifically manufactured for Renewable Energy systems.

• Refillable alkaline electrolyte

• Full depth of discharge

• 12, 24 and 48 Volt applications

• Nearly indestructible

Sizing Nickel Iron batteries

Each cell is one container.  We use 10 cells in series to make one 12 Volt battery.  20 cells in series makes one 24V battery.  40 cells in series makes one 48V battery.  Pick your capacity (100-1000Ah per cell) and the right number of cells to size your Iron Edison battery.

It's important to compare the available Amp hours in our battery to the available Amp hours in a lead acid battery.  With our Nickel Iron batteries, you can discharge up to 80% of the total capacity without any damage the cell or it's future capacity.  With a lead acid battery, it's recommended to use only 20-30% of the total battery capacity to get 5 years of life.  This means over-sizing the lead acid battery, which causes problems with the number of parallel strings and with having the proper inputs to recharge a huge battery.

Our design philosophy is to recommend a balanced system.  This includes having a battery that can be recharged in one day, with extra power to keep running your loads at the same time.  In order to figure out exactly what size battery is right for you, please give us a quick call and we will help you very easily understand our calculations.  

In general, let's compare our battery to a 24 Volt 1200 Amp hour lead acid battery.  With a recommened depth of discharge of 30%, this lead acid battery would provide you with 360 Amp hours of available capacity.  At the very most, you would have 600 Amp hours available if you discharged to 50%.  This 50% DOD will absolutely shorten the life of a lead acid battery to less than 5 years.

To achieve the same capacity with Nickel Iron, I would recommend a 500-600Ah 24V Ni-Fe battery.  The smaller 500Ah cell would be sufficient, and would provide 350Ah at 70% depth of discharge.  The 600 Ah cell would be more than sufficient, and it offers a larger electrolyte capacity than the 500Ah cell size.  With the 600Ah cell, the physical size of the cell is almost double the 500Ah cell, and there are industrial-sized lugs on the larger 600Ah cell.  There is more info below on the different cell sizes.

In this example, the 600Ah cell would offer 480Ah of available capacity with 80% DOD and 300Ah at 50% DOD.  With our Nickel Iron batteries, we are able to use a smaller battery that is going to offer much more capacity than an equivalent lead acid battery. 

Exclusive Battery Tests

Iron Edison is the only company to have tested Nickel Iron battery at the National Renewable Energy Laboratory in Golden, CO.  Our test confirmed that the cells overperform at the 5, 10 and 20 hour discharge rates.  Check your lead acid ratings, as most batteries are rated at the 20 or 100 hour discharge rate.  

Our cells provide 100% of Amp hour and Watt hour capacity when discharged in 5 hours.  When discharged over 20 hours (the lead acid standard),our batteries provide up to 118% of their rated capacity. This means you are getting almost 20% more capacity in every cell.  There are absolutely no lead acid batteries can that stand up to this level of performance - especially when you look at capacity over time.  

Cell Size Info

Please take a look at the cell sizes. All cells come in a clear case that lets you easily monitor electrolyte levels of your battery.  There are multiple cell capacities that come in the same size container.  We highly recommend using the 300Ah cell size or larger for almost every project.  By popular demand, we have increased the cell container size for the 500 Ah battery.  The 3 most popular sizes will be: 300Ah, 500Ah and 800Ah.  Please check the cell size guide (on your right), and let us know if you have any questions.

The 100Ah cell and the 200Ah cell are great for a small remote pumping station or somewhere that space is tight.  The 300Ah and 400Ah cells offer a great value, and perform extremely well in the lab.  Each cell has an integrated handle that make setup very easy. The 300 and 400Ah cells contain nearly 4x the volume of electrolyte compared to the 200Ah cell - which is why I always recommend starting your system with the 300Ah.

FREE UPGRADE:  By popular demand, we have increased the cell container size for the 500Ah cell.  The 500Ah, 600Ah and 700Ah cells are twice as large, and are my favorite battery to work with.   The volume of electrolyte in each cell nearly doubles from the previous group - this means less watering.  I really like the design of these cells, they are really an industrial battery.  I recommend the 500, 600, and 700Ah whenever possible.  The largest group of cells800Ah, 900Ah and 1000Ah features a huge electrolyte capacity, but are still managable to install and maintain.  

Charging 

The action which takes place in an Edison cell, both in charging and discharging, is a transfer of oxygen from one electrode to the other, or from one group of plates to the other.  This type is called an oxygenliftcharge equation. In a charged cell, the active material of the positive plates is superoxidized (nickel(III) oxide-hydroxide) , and that of the negative plates Fe(OH)2 is in a spongy or deoxidized state.

The normal charge rate for the battery is C/5.  This is the Capacity of the Battery (in Amp hours) / 5 hours from full to empty = The discharge current (your C-rate).  For a 500 Ah battery, the C/5 rate is 500/5 = 100 Amps per hour of charge current.  You can charge the battery using any MPPT or most PWM charge controllers and acheive specific charging voltage.

The Nickel Iron battery is able to withstand a Boost Charge, and these short duration high rate charges can be given provided that the temperature of the electrolyte does not exceed 115 F. These short charges are very efficient and cause no injury. Rates up to three times normal can be employed for periods of 30 minutes.  

Normally, we charge the battery to a voltage of 1.65 Volt per cell (or just above).  With a 12 V nominal battery, we use 10 x 1.2V cells.  When charging, this 12V battery should acheive a voltage of 16.5 Volts.  

When working with specific inverters, we may recommend using one fewer cell in series.  This allows us to acheive the higher per-cell voltages wihtout going over the inverter limits.  Because our batteries perform at up to 118% of rated capacity, the nominal loss of a single cell does not effect total capacity.    

In general, these cells like to be worked!  Charge them up and push your batteries hard with a heavy load.  You will find that your battery performs better with heavy use than if you let it sit in float charge.

Fabrication

The only 2 places in the world that make new batteries are China and Russia.  Sadly, US production ceased 40+ years ago.  Look carefully at any American made batteries currently on the market - they are very old and have not been stored with any electrolyte.  Without electrolyte, the the oxidation reaction that powers the Ni-Fe battery will quickly turn any plate to rust!  

Our renewable systems have components from all over the world.  The battery racks are from Italy, the breakers are from South Africa.  The breaker boxes and battery cables are Made in the USA.  We strongly support American businesses whenever possible. 

After throurough testing and with scores of happy customers, we produdly stand behind our brand-new batteries with a 10 year warranty.

Discharge 

In discharging the positive plates deoxidize and the oxygen, with its natural affinity for iron, goes to the negative plates, oxidizing them. It is permissible to continuously discharge up to 25% above normal (this would be about C/4).  Occasionally and for short periods, rates up to six times normal can be achieved (this would be about 1C)

Recommended max charge rate:  C/5

Recommended max discharge rate:  C/5

...Where C is the capacity of the battery in Amp hours

EX: 500 Ah battery

C / 5 = max charge or discharge rate

500Ah / 5h = 100 Amps per hour is the max charge or discharge rate 

Electrolyte

The alkaline electrolyte is comprised of KOH and LiOH.  This is potassium hydroxide and lithium hydroxide.  Consult the Materials Data Safety Sheet for proper handling information.  Always wear your saftey gear! 

Every Nickel Iron battery ships as a HazMat item.  If your battery isn't shipping hazmat, you are not in compliance, and may face serious penalties including forfiture of shipment.  Iron Edison is fully certified to handle your hazmat battery shipment.

The electrolyte of the Nickel Iron cells does not enter into chemical reaction of the cell, but acts merely as a conveyor of ions from plate to plate.  The specific gravity does not fluxuate during charge and discharge, so we don't follow specific gravity when operating the Iron Edison battery.  Speciic gravity is only important when you mix a new batch of electroyte.   Considerable variation in specific gravity is permissible, with only minor effects on battery efficency.