So I bought Nickle Iron batteries direct from a manufacturer in China about 3 years ago. They arrived in Duluth MN and sat in storage and were moved from place to place a couple of times, sat out in the MN Winter, and a few of them may have been dropped in transit. Now I am finally getting the chance to plug them in, and the manufacturer is trying to help me get them activated after storage. They are 400 amp hour batteries, 1.2V, 10 in series. Three of them seem to always measure a lower voltage than the rest, and it makes me nervous because that's probably about how many times one was dropped. Anyway, the manufacturer says:
"charge 12 hours first, discharge to 1.0 V, and then continue several cycles, until the discharge time can reach 5 hours.
Regarding the charging voltage, please use 0.2C charging for 12 hours, and then measure the battery's voltage, make a note will be ok. Please kindly note that our charging methods is constant current 80A for 400AH.
Discharge method also takes 0.2C discharge, discharge for 5 hours, measure if the voltage is 1.0v,"
So I am trying to figure out several things.
And how am I going to get my solar controller to slam a full 400AH into these batteries? It's an mppt controller, a a Tracer4215BN from Epever with an MT50 interface. It seems like the batteries come up to full voltage really fast and my controller thinks they are full and stops charging. I have it set as a 400AH battery, but the controller thinks they are lead acid. It always seems to stop charging halfway through the day and I can't figure out why. Just keep pumping out the amps lil controller! I don't know why you wanna quit while the sun is still shining! I've realized the voltage just responds differently on the NiFe batteries, and the Tracer thinks the battery is full. I'm fairly certain there is no way, no setting that will work with my mppt.
Furthermore, I am broke as I've ever been... So I really can't afford even a $100 controller. I am thinking maybe a buck converter, like this one? 1500W 30A DC-DC Boost Converter, Aideepen 10-60V to 12-90V 30A Step Up Power Supply Module Constant Current LED Driver Voltage Converter Power Converter https://www.amazon.com/dp/B07TX51XQG/ref=cm_sw_r_cp_apa_i_RAmsDb8N9B8TM I have a 900W solar array, . . . 3, 300W panels in parallel. But I've never seen them put out more than 20 Amps on my charger, so I'm not concerned about over-charging these NiFe, but it might on be on the edge for the buck converter. I have them in parallel currently. Maybe beef up it's heat-sink a little, or add a fan? I'm thinking this thing could receive the ~36V from my panels, and put out the 16.5 Volts I hear the NiFe batteries like. (Wondering if my inverter will still work if I get these things charged up all the way. . . ?)
But I don't know if it will work... Any thoughts? I would really love to prove that these NiFe batteries win the Sustainability Challenge against this new Lithium craze (even for home solar.... Yuck! I guess mass production beats best application.).
Can you help me get these things activated? I'm pretty sure they are currently float charging around roughly 5% state of charge since the controller will never put more than 20AH on them!
Please forgive my babbling. Looking forward to learning with you~
I don't have any experience with NiFe batts, but my Tracer based controller was a POS.
Specifically, it skipped absorb, jumping from bulk straight to float. I found reports from others of the same issue.
It also lacked a manual equalize option. Dumb.
The cheapo 'deep cycle' batteries I used with that controller did not fare well. An identical battery purchased at the same time which was used solo with a much cheaper PWM controller is in much better shape...
You may need to use an industrial charger to get the procedure complete. This couldninvolve breaking the battery into halves or quarters to a voltage the charger can do.
Second you will likely need a generator or grid power. Not that you couldnt do it with pv, but 80a constant.... you do not have. Likewise you could break the battery down to a doable capacity for your pv.
Is it possible that you can select "User battery" from the remote? (page 5)
Then you can select from 9 to 17V
which is an excellent range for charging nickel iron batteries.
For first charge, you can set it in the 16,5V region.
Later, you can set it to 15,5-15,6V region to get less water consumption. Absorb time is around 2 hrs
You can check. Float voltage around 14,3V
If you cannot get all the amps in one day (like having not enough solar panels), then is okay to charge them over
a time span of multiple days.
How much lower voltage are the dropped batteries?
posted 2 days ago
Thanks for your feedback everyone.
Interesting to hear you've had trouble with your Tracer. I may be able to support your POS claim! I had a new lead-acid battery go bad after 3 years with this controller (about 50% of expected life?).
Steven I was having trouble getting your link to load. . . but yes, there is a User setting, but I have found it will not let me adjust the Voltage in the ranges you mention. (might not be the exact same Tracer model?) I concluded the same thing, that I might take many days to add 400AH to the batteries, but eventually they will charge up (assuming we use less power than we generate! lol)
Also I am happy to report I am no longer measuring lower voltages on certain batteries. They seem to have normalized, so I have increased hope for this activation process! I think I just need to get some Amp Hours into these babies~
Steven Di Maira
posted 1 day ago
- Buck converter, I would not call it stupid. However there a caveat on this.
With this DC/DC converter you can set the output voltage (good), but you cannot alter the maximum output current.
The load (batteries) can take whatever current they want.
The risk is that you can overrun the max current the DC/DC converter can supply. (can be seen in some of the reviews )
It would require manipulating the charge voltage very carefully, in order to avoid overload/damage of the converter.
A bench power supply, something like this has the advantage that you can both set a limit to the voltage and the current.
One thing i failed to notice earlier, your array at 900w should be close to 50a charging near absorb voltage if all is well.
Another, that your battery is only 12v thought it was higher. In a guide for ukranian made edison batteries, they mention using one less cell if your gear cannot be set the the higher voltage. That cell could be cycled in periodicaly or left out until you get another controller.
In full sun.ypur array has higher power available than the control can pass. Its another great excuse for an upgrade controller!
Steven Di Maira
posted 1 day ago
About solar capacity: good point!
If you respect the cable sizes, it is possible to wire a solar panel directly to the NiFe batteries.
I would not recommend to do this permanently. But if you just want to get the amps in (a one time pass)
it will work.
The battery will pull the voltage of the solar panel to it's own level (constant current charging).
Do keep an eye on the charge voltage and quit when needed. (at around 17,5- 18,5V)
They NiFe cells will boil the excessive charge as hydrogen. (don't use an airtight container for the batteries)
Check water levels.
And tomorrow is the circus! We can go to the circus! I love the circus! We can take this tiny ad:
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