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bcg1976 avatar image
bcg1976 asked

Constant current charging for NiCd block batteries

I'm running a multiplied 24/3000/70 and an MPPT 250/100 and have constructed a 20 battery saft SMB277-2 bank in a parallel/serial config to give me what should be around a 540Ah battery at 24 - 30v.

As I understand it, these sized batteries want around a 50A current constantly applied with a voltage ideally at 1.4v per cell.

Is there any way to reasonably achieve this with the victron kit I have? The batteries owe me nothing besides a headache when I need to get rid of them so I'm not too fussed if we shorten their service life with a good enough solution.

Thanks.


battery charging
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3 Answers
snoobler avatar image
snoobler answered ·

Datasheet on this page:


https://www.saftbatteries.com/products-solutions/products/block-nickel-batteries-sble-sbm-sbh


0.1-0.2C5 rate

1.45-1.70V/cell absorption

1.40±.01V/cell float



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kevgermany avatar image
kevgermany answered ·

You'll overcharge with your solution. Apart from current, you must cut out when the voltage drops.

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bcg1976 avatar image
bcg1976 answered ·

But is there a way to get current constant on the multiplus? Or at least change the current / voltage curves to something more nicd friendly?

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