Can I connect a 200W solar panel to my 12v 150ah Lifepo4 while using the Trolling Motor? Vs. skip the battery and directly from panel->motor (sunny)

[gemsolarpo]

Sorry if this should be in the beginners section.. i know this might sound very newbie but here's my setup:

• 12v 150ah lifepo4 65lbs brushless trolling motor on 11' inflatable raft, 3 adults with camping gear
• folding 200w solar panel with PWM controller

Can/should I connect the panel to the battery with the motor connecting and being used, say, pulling ~80W? Will this cause any issues? If it's sunny enough is it more efficient to just directly connect panel (alligator clips from the PWM onto the alligator clips of the trolling motor?) ?

We're trying to do 50km total in range (~30miles), and I was skeptical my 150ah could make it the whole way so I thought adding a solar panel would make the trip more reliable.

Thank you so much!

 

[chrisski]

Add the panel with a Solar Charge controller and the connection will be fine.

I'm a bit skeptical this will add any useful distance. A 200 watt panel will only provide 6-12 amps in good sun conditions. My 500 GPH bilge pump runs at 6 amps.

 

[cs1234]

If it's lightweight enough, I see no harm in having a solar panel available on a trip to the wilderness. With the right leads, you can even use a solar panel to start fires. ?‍

 

[efficientPV]

I was shocked when Ampere Time suggested just connecting a solar panel to the battery with no charge controller. They made no mention of what might happen to other electronics after the BMS disconnected. It would be fine while the motor is drawing some load and the battery is nowhere near full charge. I don't like to fully depend on a BMS. I have a couple extra panels connected to mine and have a buck converter set to 13.8V. At worst the gain is zero from it and most time there will be a current boost. You won't need to think of overvoltage.

 

[chrisski]

I’d you connected a 200 w panel to a battery directly, you would trip the internal battery BMS as soon as it’s connected.

A lot of people think a “12v” panel puts out that, but it will put out between 16v and 22v, we’ll above the 14.5 or so volts the BMS is set.