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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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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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