Solar Battery maintainer?

As I don't drive the XJ as often as I should or actually even would like to the battery drops to a point that's too low from time to time. Picked up a nice solar cell that gives a steady 24V in sunlight and I'm wondering about it being used as a "maintener".

I figure I can plug it into an accessory outlet and should see 24V at the battery? Or is there a voltage regulator someplace in the system that's making me see 12V and change? Also any adverse effects to putting that on the gel cel battery? I use the Sears one.

I'm not sure about a 24V cell, but I use a 12V cell with alligator clips for the positive and negative post on the battery. When I store my extra vehicle, I place the cell on top of the dash binnacle inside the vehicle in direct sunlight. I then run the alligator clips through the door and under the hood directly to the battery. This was a harbor freight purchase ($14.99 I believe) and it has worked reliably for me for years. It's maiden voyage was Black Rock City at Burning Man in 2006 and it has worked perfectly ever since.

I have the harbor freight unit: http://www.harborfreight.com/15-watt-solar-battery-charger-68692.html it is actually (inside the manual) listed as a 12/24V unit and when I put a meter across the output in full sun it did generate 24V

I b;ieve that the 12/24 V means that can be used for either system. As long as there is a diode in the unit to prevent overcharging. No reason it should not work as a maintainer. I have a similar unit that I have used on my XJ. It now resides in my Dub,as that gets the least usage.

I have a 12v, 4 amp solar trickle charger I use for my boat battery. I also use it for my trolling motor deep cycle battery. Always charged. Love these things. Only $22 at the local RV shop.

I ended up going to HarborFreight again and bought the voltage regulator gizmo hookup that they have. It will work with up to 100W so it has future expansion options And it was only $20 with a coupon

Absolutely what Johnnywalker said! Must have the unit that prevents overcharging. My friend killed a new marine battery for his boat because of overcharge from the harbor freight solar panel....

The solar panels I came across in the past were always rated between 13 and 15 volts. I have not heard of a 24 volt unit. For a 24 volt system we used to tie two panels in series. I guess making 24 volt units could be of value to many. For a 12 volt system, the correct voltage regulator will keep high voltage in check.

I have a Sunsei solar panel rated at 22.5 watts at 15 volts for about 5 years which charges dual Optima 800 amp batteries and no voltage regulator. It have maintained the batteries for more than 3 years while I was out of the country. Those batteries remain at about 12.6 volts all year long. If I was using only one battery or a higher rated panel I would have added a voltage regulator to the mix.

A funny thing though is, several manufactures marketed a 6 watt unit to be used as a battery maintainer which were proven useless in many automobiles. 6 watts will actually charge less than .50 (1/2) an AMP at 12 volts in peak sunlight and nothing at all after sundown. Many users complain of dead batteries while using this/these units. To maintain a battery it need to be charged at 1 AMP and maintained this way 24 hours and 7 days per week. This especially true in newer vehicles with all that parasitic electronics.

Kejtar said:

As I don't drive the XJ as often as I should or actually even would like to the battery drops to a point that's too low from time to time. Picked up a nice solar cell that gives a steady 24V in sunlight and I'm wondering about it being used as a "maintener".

I figure I can plug it into an accessory outlet and should see 24V at the battery? Or is there a voltage regulator someplace in the system that's making me see 12V and change? Also any adverse effects to putting that on the gel cel battery? I use the Sears one.

Click to expand...

Really dont like these cells.Very expensive and of not much use..:yap::yap:

Not of much use for what?

I use the $15 one from Harbor freight as does my father. My XJ and his pickup are not used that often.

They work great! His pickup sat from November to February in a NY State winter and it spun over like new after sitting for 3 months in one of the colder winters we have had.

DonnieStoddart said:

As I don't drive the XJ as often as I should or actually even would like to the battery drops to a point that's too low from time to time. Picked up a nice solar cell that gives a steady 24V in solar panel and I'm wondering about it being used as a "maintener".

I figure I can plug it into an accessory outlet and should see 24V at the battery? Or is there a voltage regulator someplace in the system that's making me see 12V and change? Also any adverse effects to putting that on the gel cel battery? I use the Sears one.
Really dont like these cells.Very expensive and of not much use..:yap::yap:

Click to expand...

I was taking about solar cells