Nickel Iron (NiFe) Batteries

NiFe batteries are Go-To-Battery for longevity, the main drawback is, these Battery have a lot larger footprint and are Very Heavy & Not suitable for wall mounting due to there Weight.

We purchase New, unused NiFe Battery from the Manufacturer that has made batteries for the Military for over 30 years, we Do Not sell re-conditioned NiFe Cells like some sold on eBay ...we get there complaints !

Durability;

The ability of these batteries to survive frequent cycling is due to the low solubility of the reactants in the electrolyte. The formation of metallic iron during charge is slow because of the low solubility of the ferrous hydroxide. While the slow formation of iron crystals preserves the electrodes, that limits the high rate performance: NiFe batteries charge slowly & only able to discharge slowly, simular to Lead Acid batteries.

Nickel–iron cells should Not be charged from a constant voltage supply (unless Condition Charging), since the cells can be damaged by thermal runaway, the cell internal voltage drops as gassing begins, raising temperature, which increases current drawn and so further increases gassing and temperature.

IMPORTANT NOTICE: Modern Hybrid Battery Inverters have a Max. Charge Voltage of 60V DC, if you are installing NiFe Battery bank, you are better off only purchase the follow minimum Cell Quantities !

NiFe (nickel-iron) battery cells are all rated at 1.20V, no matter the size of the battery, however the Cell Float charge voltage is typically 1.48~1.50 volts per cell. Higher voltage can be used to ensure all cells in the battery bank are fully charged, and to help equalize the voltage across the battery bank.

Example of Charge Voltage of NiFe Battery bank;

• 12V System =   9~10 Cells in Series, Float Charged to 1.50V per cell  = 13.5~15 Volts.
• 24V System = 18~19 Cells in Series, Float Charged to 1.50V per cell  = 27~28.5 Volts.
• 48V System = 38~39 Cells in Series, Float Charged to 1.50V per cell  = 57~58.5 Volts.

The most common Hybrid Battery Inverters are 48V, and only charge to Max. 60V DC, so NiFe Cells need to be Configured in Series to be Charge to 1.65V each, as that provides better performance characteristics on Hi-Amp Power consumption, even though the Cells are Rated at 1.2V, when Charged to 1.65V they perform better, and most modern 48V Inverters are Only capable of Charging up to 60 Volts DC.  For Special Hi-voltage applications, banks of NiFe battery can be configured is Series up to 750V DC.

Distilled water is required to maintain Electrolyte levels, we recommend Purchasing $80 Distilling Kettle , that should be operated off your Solar, to produce FREE Distilled Water.

The Pros & Cons:

1. Our NiFe batteries come with an 8 year Warranty.
2. A majority of NiFe batteries are fully operational after 50+ years of service, and most will likely be for another 50 years, if you keep on topping-up &/or replacing or filtering the Electrolyte as needed, as that provides a "Like New Battery" again !
3. Be aware some Chinese manufacturers Re-furbish X-Government Cells & sell them as New !
4. NiFe batteries require a larger storage footprint & are heavier at approx. 45kg per kWh, compared to LiFePo4 batteries at approx. 8kg per kWh.

3 things that can cause NiFe battery capacity problems:

1. Inadequate Charge Current.
2. Contamination of electrolyte by Top-up Water.
3. Incorrect electrolyte Concentration.

When it comes time to Replacing the Electrolyte, use this Battery Electrolyte Mixing Calculator to work out the correct quantities of Chemicals and Distilled Water required for each battery !

We can supply an Optional Automatic Gravity Feed Distilled Water Battery Filling System, that provide a maintenance free operating system, using quality Stainless Steel Filling Straws & 6mm Silicon at the Cell, and Plastic Air line back to the Reserve Tank. 

This Electrolyte Chemical Mixing Calculator provides the correct mixing quantities !

See if you need to Clean-n-Service NiFe Cells & Replace the Electrolyte !

If you are looking to Replace the Electrolyte, we can Import the Chemicals, however that may be more expensive than sourcing locally, the Chemicals for a 500Ah cell cost approx. $45 per Cell if imported.

EG: 40x 500Ah Cells requires 75kg of KOH and 5.6kg of LiOH chemicals.

25kg Bag of KOH from Bosca below Costs $95, and 500g LiOH on ebay costs $150, use links below to Purchase;

• KOH: https://bosca.com.au/
• LiOH: https://www.ebay.com.au/

Recommended NiFe Charging Voltages;

As most Hybrid Inverters only have a 60 Volts DC Charge Rate, so for a 48V~51.2V Battery System, you only need 37~38 Battery cells connected in Series Charged to 1.57V each, where in areas with Very Cold Weather it is better to Charge the Cells to Max. 2.2V each, meaning you would have to remove Several Cells during Winter or Colder Weather conditions.

Download this .pdf NiFe Battery Charging Manual

1. Constant Current Charge method:
   In Normal Temperatures, the Charger should be set at 1.55V cell × cell QTY.
   In Colder Temperatures, the Charger should be set at 2.2V cell x cell QTY.
   (E.G. Normal Temperature is 20℃ ±5℃. 38x NiFe Cells = 38 x 1.55V =59.8V, in Very Cold Temperature a Min. of 27x NiFe Cells = 27 x 2.20V = 59.4V can be configured)
   
2. Constant Voltage Current Limit method:
   The charge should be set to 1.55V/cell～1.75V/cell × cells, the current limit is set at 0.2 C5A, when the charge current decrease to 0.02 C5A, then changed into float charge method, the voltage range of the float charge is 1.48V/cell～1.50V/cell × cells, the current limit is 4mA/Ah～6mA/Ah.
   (E.G. 38x NiFe Cells = 38 x 1.55V = 59.8V) As most Hybrid Inverters will Only Charge to 60 Volts DC.

With normal temperature of 20℃ ±5℃, the Charge voltage should be adjusted properly.

In general, if the temperature exceeds 25℃, the charge voltage decrease by 0.003V per 1℃.

When the temperature is Less than 25 ℃, the charge voltage increase by 0.003V per 1℃.

Problems with New or batteries left Uncharged for a long periods ?

If your battery bank shows signs of not lasting as long as they used to, e.g. SOC & Voltage dropping off quicker than they should or used to do, there are several possible reasons why.

One could be, they are Not being Charged properly. This could be lack of daylight hours during Winter or consistent cloudy days, causing reduced charging or your Inverter DC Charge Voltage may be set to Low. Commonly each NiFe Cell need to be Charged to 1.6V each, if you have 36 cells (48V System), the Charge Voltage is multiplied by 1.6v x 36 =59.4V. So you need to set the DC Charge Voltage to Match your Cell Quantity, Equal to or lower than the Inverter Max. DC Charge Voltage.

There could also be impurities being introduced into the electrolyte, if Not using good quality Distilled Water (Not de-ionised water), that can reduce the possibility of problems that can arise from using Tap water.

If the Batteries are older than 7 years, it could be time for an electrolyte replacement, if so, we advise you check the Electrolyte Specific Gravity (SG). New electrolyte SG should be between 1.21 and 1.23, If under 1.18 or significantly higher than 1.23, electrolyte may need to be replaced if Not Charged recently.

Batteries Not used enough or left Uncharged for long periods, will cause the rated capacity to drop, in this case you will need to re-Condition Charge the battery Cells back up to 1.65V each.

NiFe batteries loved to be worked and thrive on hard work and cycling. So don't be scared to work them, you won't shorten their life, just make sure the Electrolyte Level remains above the Min. Fill Marks.

Ensuring the batteries Electrolyte do not fall below the LOW level mark on the battery casing is important, Failure to do this will result in the capacity of the battery being reduced, and can also create the cell to produce more Hydrogen than is normal, and could Cause an Explosion if there is a static spark.

Keeping the electrolyte between the Low and high level marks & using Red Cell Fill Caps, means that the Hydrogen off-gassing will always remain at a low concentration & not ignite.

This Bank of Nickel Iron Batteries has our prototype Automatic Watering System.

Finished Wiring of 5kW Inverter & Generator Plug.		5kW LUX SNA OFF-Grid Inverter, with 35kWh NiFe Battery Bank, 4.2kW Petrol Generator & Automatic Watering System.
42x 600Ah with Auto Watering.		42x 600Ah Batteries.		B3 Steel Racking *$1'900.
Automatic Watering System.		Lower Bank Batteries.		Racking Design Options.
Two Tier Steel Racking *$900.		Battery Racking is Optional.		1'200Ah Racking Front.
Painted Steel Racking *$900.		Accessories that come with NiFe Battery Bank, Battery Cables are also included.		40x 1200Ah Batteries come in 5x strong plywood Crates. =57.6kWh Energy Storage.
NiFe 1200Ah Battery is the largest NiFe capacity.		1'000Ah, 1.2V Batteries.		1'000Ah, 1.2V Batteries.
1'000Ah, 1.2V Batteries.		800Ah Battery.		10x 500Ah Crated. This is a 12V 6kWh Bank.
400Ah Batteries.		300Ah Battery.		Six rows of NiFe Batteries, banks can be up to maximum 750V DC.
Old Steel Racking Design.		12V Home made Pipe Racking.		24v Battery Configuration.
Tools & Accessories included with Battery Bank purchase.				Strong Double Plywood Battery Crates.

HISTORY of Nickel Iron Batteries

In 1901 Thomas Edison developed this battery technology, it has long been considered one of the perfect battery technologies, and time has proven them against all comers!  You can still purchase some of these Vintage 100yrs old battery, and they still work, this has a lot to do with the fact that the energy is actually stored in the Electrolyte.

Edison once said, “A good idea is never lost, even though its inventor or possessor may die without publicising it, it will someday be reborn in the mind of another.”  See these Heritage images (1)(2)(3)(4)(5)(6)(7)(8).

The latest designs of these days are rated and reported to cycle over 10'000 times, that's 30+ year daily cycles life span, where the electrolyte only need to be replaced after 7~10+ years, covered below in more detail.

Worldwide Users Report: NiFe battery's & Electrolyte have cycled over 10'000 times;

1. That equates to over 27years, with Electrolyte lasting between 7~12+ year periods, meaning you only have to Replace or Filter the Electrolyte, the electrolyte replacement cost is approx. 5~7% of the battery cost, that will provide like new condition for the next 10+ years.
2. Battery's Liquid level need to be kept above the internal plates, checked every 6~12 months if you have a large reserve tank on a Automatic Watering system.

Nickel Iron (NiFe) Battery Electrolyte consists of;

• Potassium hydroxide (1.2g/cm3) is an inorganic compound with the formula KOH, and is commonly called caustic potash.
• Lithium hydroxide (20g/L) is an inorganic compound with the formula LiOH. It is a white hygroscopic crystalline material. It is soluble in water and slightly soluble in ethanol, and is available commercially in anhydrous form and as the mono-hydrate (LiOH^.H₂O), both of which are strong bases. It is the weakest base among the alkali metal hydroxides.
• If you already have Solar or just want to manufacture your own Distilled Water, you can purchase a $70 Water Distiller on ebay, these 750W units make 1 litre per hour.  However, a lot of people use reverse Osmosis Filtering or Charcoal Filters to purify there Rain or Tap water for topping up the Electrolyte.

What is the Correct NiFe Electrolyte Chemical Mixing Quantities ?

This Calculator automatically provides the correct Chemical Mixing Quantities.

NiFe batteries are now manufactured with stronger and improved components, a NiFe battery bank is made up of individual cells, all cells are rated @1.2 volts each, No matter the size of the cell or battery bank.  To make a battery Bank to a specific Voltage, you simply add cells together until you get the require voltage.

The key to Nickel Iron (NiFe) Batteries long life lies in quality manufacturing, the VARTA cell technology was designed for use moving & vibrating situations like vehicles, trains & mining equipment etc., providing a very long working life.

NiFe batteries will continue to work like new a long past the 10 year manufacturer guarantee period, and have long been considered the best green energy battery for decades, they are 100% recyclable, with no dangerous materials including the electrolyte, NiFe batteries are a Non Acid battery.

NiFe battery are widely used as DC back-up power supply for Solar Energy storage and used in homes, businesses, vehicles, remote telecommunications, railway, mines, tractors, petrochemical, oil and gas, electricity industries, and other renewable power applications.

Nowadays, more and more countries have attached great importance on environmental protection and advocate using green energy. Because of NiFe batteries high reliability, long service life, lower maintenance cost, pollution-free and other positive characteristics, NiFe batteries are rapidly replacing Lead-acid batteries in wide ranges of applications, especially in off-grid systems using Solar, Wind, Aqua as well as power produced by Fuel Generators, NiFe are also be used in load shifting applications, e.g. charging the batteries using cheaper off-peak power, usually at night.

We can order NiFe batteries Casings made from either Polypropylene (PP) or Methacrylate butadiene styrene (MBS), MBS is also known as impact modified Styrene Methyl Methacrylate (SMMA). This polymer has excellent clarity, high stiffness, high impact performance and easy process ability.

Advantage of NiFe Batteries:

1. The Cheapest Long Term Battery Investment Cost per kWh.
2. Wide capacity range: 100Ah~1200Ah.
3. SGS, GOST, IEC60623, ISO, CE, UL certificate.
4. Long life: 15~40+ years.
5. -20°C~50°C Operating Temperatures.

Characteristics:

• MBS (Methacrylate Butadiene Styrene) is an Opaque Casing modifying agents used to improve the impact strength.
• PP (Polypropylene) is a Transparent battery Casing, material is Hard, but Fragile in low temperatures.
• Excellent charging efficiency and smooth discharge voltage.
• High reliability without sudden death.
• Ability to withstand ultra-high and ultra-low environmental temperatures.
• Withstand physical and mechanical abuses.
• Exceptionally long & reliable service life (up to and over 50yrs).
• Pollution-free, total green energy and recyclable.
• Low Self-discharging, not an issue when being charged on a daily basis.
• No emission of corrosive gases, Safe from flame & explosion.
• Pollution-free and excellent mechanical strength.
• Convenient for installation and low maintenance.
• Comply with SGS and GOST standard.
• Availability to design and manufacture other model according to user's requirements.
• Electrolyte weighs approx. 1.2kg per litre.

Initial Charge:

• New battery stored for more than 6 months should be charge at 0.2C 5A for 8 hours, then discharge at 0.2C 5A to 1v per Cell.
• Repeating above charge and discharge for 3-5 cycles.
• If the discharge duration isn't less than 5hours and the battery voltage isn't less than 1.00VDC per Cell, the battery can be put into operation according to normal charge.
• C5 means the output capacity of the battery discharged to cut-off voltage at 1.0V with 5 hours rate at 20°C. Namely-nominal capacity, Under normal circumstances, the battery should be charged by normal rate (0.2C 5A).
• In the case of emergency, the fast charge method ( 0.5C 5A ) can be used.
• The battery must be charged at normal rate (0.2C 5A) for 12 hours when it is overcharged.

NB: Some of the Measurements & Weights in the downloadable .pdf documents are not totally accurate.

NiFe Customer Reports:

• Read what Customers have reported about there NiFe Batteries.