Charging Li Ion 18650 with smartsolar mppt

DIY
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Hi,
I’ve been working on a 3D printed solar drone boat project and I just want to hear from some experts before testing my solar charger out.

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These are my settings in my Victronsmartsolar mppt 75/15 for charging a 4s3p li ion 18650 battery pack, salvaged from a broken escooter. I’ve set the charger to charge the battery up to 4.1v per cell and at a charge current of 5A (which is below 1C however I don’t know the actual mah rating of my battery)

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The boat pulls around 60-70w while running but can go higher if I’m using full throttle, so is it safe to connect the load to the battery and not the dedicated load output on the controller? This way the current isn’t limited by the charge controller and won’t blow the fuse.
Thanks

2

Your voltage is OK, 5A max should be OK for 18650 cells, 3 in parallel. I suggest setting max absorption time to 1h, maybe even 30 mins. 10 hours is way too long if they get stuck at max voltage during charge.

You should connect the motor to the battery as motors can have high start up current the MPPT may object.

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