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alaskannoob avatar image
alaskannoob asked

My Pylontech Batteries are Full & This Worries Me

Click bait title, but I'm in Alaska and our 38KWh of Pylontech remains between 90 and 100% SOC because we have so much sun. When the sun goes down, night time loads might bring the batteries down to as much as 90% but there is no question in the morning they will be quickly charged to full again and all loads will be powered by PV for the rest of the day.

Is this bad for the batteries to spend the whole summer like this?

I thought there were charging profiles for keeping batteries full OR for battery life that could be selected, but I have to connect these batteries via DVCC so the batteries tell the Victron system what they want. So I'm not sure I can do anything about this "problem."

Thoughts?

Pylontech
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3 Answers
kevgermany avatar image
kevgermany answered ·

It's not a problem, or anything to worry about.

The batteries are designed to go to 100% and stay there. The battery life settings are for lead based chemistries only.

Lithium Ion is a different story. These shouldn't be kept fully charged for extended periods.

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Duivert NL avatar image
Duivert NL answered ·

No problem at all, in wintertime when there is almost no PV i set the system on keep batteries charged in vrm every year

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Alexandra avatar image
Alexandra answered ·

@AlaskanNoob

The system will charge as directed by the batteries. Also victron don't keep them at full even when 'full'.

Note the voltages (are programmed to) move between 52 and 51v anyway when down at float. Even though it says 100%. Sometimes they will go to 99%.

In any case you aren't/can't keeping them at 100% all day every day. Even on a keep battery charged system the system floats and re-bulks them (so they move up and down).

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