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cybermaus avatar image
cybermaus asked

Sodium battery and Smartsolar 100/15 and 100/30

Is anyone using Sodium batteries together with a SmartSolar.


I have both a SmartSolar 100/15 on and a SmartSolar 100/30 (they are on different vehicles) and in both of them the lead-acid battery is getting bad.

Instead of replacing them with LiFePo, as is common nowadays, I am considering Sodium (Na-Ion) batteries. They charge the same CC+CV curve as LFP, or so I am told, but with different voltages, and I noticed I can set those voltages in the Smart Solar devices.

(well, nearly all of them, Sodium can discharge to well below 10V without problem, but 10V seems the lowest I can set)


Anyone is already doing this? Any experiences?


PS: yes, I am aware of the problem with engine Generators/Dynamo's and Lithium high current and sudden BMS shut down. Is not my primary question, though I am open for experiences in that too.




MPPT SmartSolar
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6 Answers
Mike Dorsett avatar image
Mike Dorsett answered ·

Found this on Wickipedia...

Only problem with allowing discharge below 10V, is that most inverters will not work with voltages this low. However, this much aside, the critical thing is the ability to set the absorption and float voltages correctly, and observe the max charge current for the battery.

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cybermaus avatar image
cybermaus answered ·

Yes, using the power is important. Which means inverters should be possible to go down to 16V (for a 24V system). But also, the obsorb and float voltages should be able to go to 32V, and I wonder if anyone has done that .

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klim8skeptic avatar image klim8skeptic ♦ commented ·
@cybermaus the trouble with such low battery voltages is that the battery current required goes up to meet the load output.

A 2400 watt load will require a batt current of 92a @ 26v, 100a @ 24v, 150a @ 16v. (ignoring conversion losses)


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cybermaus avatar image cybermaus klim8skeptic ♦ commented ·
That is correct of course. But given there are people running inverters of 12V, I think 16V should be doable. But yes, 12V Sodium inverter systems would be ludicrous, with the 8V unrealistic low number. Again, for inverters.


But note my question was originally about a 100/30 solar charger. I am running a 24V system in a camper, without any inverter. And I would really like to use Sodium.

(actually, I have a small 500W one for ad-hoc use. Lets not consider that part of the system)


Because while 16V would be low for a 24V system, I think companies like Victron should really be thinking about making this step, or at least allowing for the 32V float levels required. Sodium just has a lot of environmental advantages, it being an abundant rather than rare metal.


PS: The picture above is likely a 2x 48V or single 96V system (based on the two stacks of 16 cells). Also making the 32V or 64V floor voltage more workable. After all, there are people running inverters of 12V

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thamnu avatar image
thamnu answered ·

Hello together,


I'm planning to use sodium batteries with BMS in an off-grid application with 2x Smartsolar 100/30.

This topic is dealing with the chich charging program, but i can't seem to find which one I need to select?

Best regards

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cybermaus avatar image cybermaus commented ·
Can you rephrase your question a bit? Not sure I understand.


I have learned a bit since though. If you install VictronConnect, you can install "Demo" equipment, and you can see which voltages you can set, and the Orion XS, the SmartSolar, and some of the inverters *can* in fact be set to the needed Sodium voltage ranges.


Also, I have used my SmartSolar to charge 4 cell (12V) Sodium batteries, with success.
Just copy the LFP to a new name (that way it has no equalize) and set the new 16V top limit for the charger, and the new 9V bottom limit for the inverter.

You do want to derate the inverter a bit to only 9/11 of the original rating.


But ideally, I think you should make a 24V system really, and that means waiting for the Orion XS 12/24.


For now, I stopped experiments, not because they failed, but proper Sodium cells means re-ordering the footprint of the equipment, so next winter.

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thamnu avatar image
thamnu answered ·

So basically we ordered two sodium 12v batteries to use parallel.

They will be charged by a smart solar 100/30. Not sure about the arrangements yet but probably also parallel.

There is consumption by chargers for hobby rc models, an Inverter (not sure about the type but it's 1kW victron)


The question is if there is a setting or a profile for the smart solar 100/30 to set the proper cell voltage or top and bottom limits.

Or do I have to set the limits manually as you said?

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cybermaus avatar image
cybermaus answered ·

Are you sure you do not want both series to 24V? Unless if you are stuck to a pre-existing car alternator or something, or really need 12V for some reason, go for 24V. Everything works better at 24V


Anyway, to answer your question:

There is no preset profile. Select a LFP battery as basis, and next manually change the voltages. Then save it as a personal named profile.

Do this first on a demo device on Victron Connect.



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thamnu avatar image
thamnu answered ·

Okay thanks for the answer,

Most of the personal rc chargers don't support 24v sadly, so we go with 12v.

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