Solar Trickle Charger?

[Michael-Rhonda]

Greetings – any suggestions on a solar trickle charger to keep batteries charged over the winter in Colorado? There are some good posts from 10 years or so ago but I’m looking for any updated suggestions. My TM is stored at a storage facility with no electricity. I would like to keep the batteries in the TM. I use a battery disconnect switch. A quick look on Amazon and Harbor Freight yields several possibilities. Suggestions on brands? How much power (I saw 5 watts suggested)? Thoughts on mounting? Any other ideas? Thanks!