question

asbjoern85 avatar image

Disabling charging on SmartSolar at negative temperatures

Hi,

I have a Victron Smart Solar MPPT 100/20-48 and I recently replaced my AGM battery bank with a LiFePO4 battery that is rated for charging down to -15°C at 0,2C. I was going to set the Smart Solar to disable charging below -10° to be on the safe side, but it won't accept a value below 0°.

Is this something you're planning to change with a future firmware update?

Another feature request on the same subject, it would be nice if the Smart Solar could charge at full power above a set temperature, and a lower charge rate at lower temperatures.

Lithium Batterymppt smart solar
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3 Answers
Thiemo van Engelen (Victron Energy staff) avatar image
Thiemo van Engelen (Victron Energy staff) answered ·

Hi,

I was not able to test with exactly the same MPPT, but with a SmartSolar 75/15, running firmware version 1.54 and VictronConnect v5.37, I was able to set the low temperature cutoff to -10 degrees. Can you perhaps test again with this combination of firmware and VictronConnect?

Kind regards,

Thiemo van Engelen

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I tried it again this weekend, it doesn't save the setting. I have tried many times with different values including -10. If the value is below 0 it doesn't save.

I have a SmartSolar 75/15 at home, I can test it with that one.

asbjoern85 avatar image
asbjoern85 answered ·

Any input on this question please Victron? @mvader (Victron Energy)

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blutow avatar image
blutow answered ·

I don't know about the setting, but can you share what battery you are using? Are you sure the -15c rating isn't a limit for discharge? I've never seen a lifepo battery that allowed charging anywhere near that low (unless you count the batteries with internal heaters that heat things up with the charging current before starting to charge the cells). I'm not saying it isn't possible, but just curious if there is something special about the chemistry or how they are allowing such a low charge temp.

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It's a rebranded battery from Farco.no. The specs allow a 0,2c discharge down to -15°. I'm a bit sceptical, but there is a 5 year warranty.