Thunderbolt 1.5 watt solar charger

Hi,

I'd suggest you return it. However, it is so small that no controller is needed.

I'd aim at no less than 60 watts per 100 amp-hours with a good controller myself.

Question along the same lines but different reason ... I bought a 2 pack of panels from Costco a number of years ago that look just like that ... curious if a controller is needed to prevent my or the OP's panels from draining the battery during darkness? Or is that not a possible scenario?

On an earlier thread I posted an unregulated transformer charger 18-volts open circuit 800 milliamps at 12.0 volts...

Maintenanced a new totally disconnected flooded group 29 battery at 13 62 volts @ 25c.

No hypothesis. This is reality. React to it as you wish.

gkainz wrote:
draining the battery during darkness? Or is that not a possible scenario?

These tiny panels usually have a blocking diode to prevent drain

Saint Augustine wrote:
It is a trickle charger or float charger. It simply maintains the voltage. I have used a plu in "float" charger on my tractor battery for several winters with success. Starts immediately. Neither of these devices are meant to "charge" the battery.. Some of you might try "bib gig" the concept. I was hoping for an informed response. Thanks anyway.

A "Tractor" is a far cry from an RV. Tractors do not have any external draw circuits at all. An RV may have many devices pulling current from the chassis battery. That is why there is so much negative feedback on a charger maintenance device such as you mentioned, which has a very low charge current output. ... but if it works for you, then great. If it doesn't, you will soon find out.

My rule: if the buyer and the seller are tickled pink that's an agreement made in heaven...

-NUFF SAID

Saint Augustine wrote:
It is a trickle charger or float charger. It simply maintains the voltage. I have used a plu in "float" charger on my tractor battery for several winters with success. Starts immediately. Neither of these devices are meant to "charge" the battery.. Some of you might try "bib gig" the concept. I was hoping for an informed response. Thanks anyway.

I did respond to your query in the third post of this thread when I wrote;

beemerphile1 wrote:
The output is so minimal you can leave it connected 24/7/365 without concern...

No need for me to "Bing" the subject.