Solar Powered Battery Chargers

[Big Water]

I'm buying a 24v trolling motor for my boat, but store the boat where it will not have 120v service to charge the batteries.  My question is whether the solar battery chargers are sufficient to charge these batteries in the course of a week in fall/winter.  Also, do they make a 24v solar charger or will I need to buy 2-12v chargers and seperate the batteries during charging?  My last option would be pulling out both batteries weekly, but I'd like to avoid this.  Anyoneone have experience with these for this purpose?

 

Thanks,

 

Doug