Deep cycle battery found empty...

[Damienmumu 0]

Hi,

While service my trailer sailer I found my deep cycle battery was no longer holding my the charge.

After extracting from the boat, I realised there is no fluid left in the battery and it was kept on the solar panel.

Do you think it is permanently damaged or shall I try fill it with demineralised water and see if battery is still fine.

If it is considered dead, shall I look at purchasing a sealed battery??

Thanks for your help.

Damien

[2flit 52]

If a flooded cell is dry and been charged; you have a permanent loss of capacity in the area of the 'dry' plate.

If there is 'no fluid' in the battery and it was being charged (as in charged dry). The entire battery is history. Get a charge controller for the solar panel and buy another flooded battery, then you should be fine. 

[Island Time 1,290]

Its stuffed.

"Sealed" batteries are not sealed, they are valve regulated, and can still off gas if overcharged.

You need a proper 3 stage regulator for your solar panel. If it was at float voltage it would have taken years for the battery to get low on electrolyte,  let alone dry. 

So, if you have a regulator for the solar, its not working properly, or not programmed properly. If you dont, you need one.

 

[Damienmumu 0]

Thank you for your advices!

I have a solar regular but I understand it is a cheapy: https://guide.alibaba.com/shop/gxg-1987-cmp-12-20a-12v-24v-solar-charge-controller-solar-control-regulator-solar-panel-battery-regulator_1026293016.html

I guess it would pay I install a better one... any advice on brand or model... for resonable budget?

I had a 50AH battery that seemed sufficient at the time connected to a 20W solar panel. I am wondering if I should keep 50ah capacity or should up it to 75ah. Also should I better invest in an AGM battery rather than wet-cell?

I run: VHF, small depth sounder, 2 small LED lights, small hand held GPS, 2 phones to charge, nav lights (hardly as we don't navigate at night). Maybe plan to install a stereo at some stage...

Thanks.

 

[2flit 52]

11 hours ago, Damienmumu said:

... any advice on brand or model... for resonable budget?

I had a 50AH battery that seemed sufficient at the time connected to a 20W solar panel. I am wondering if I should keep 50ah capacity or should up it to 75ah. Also should I better invest in an AGM battery rather than wet-cell? The AGM battery will be even more susceptible  to being run dry. They have a 9 pascal vent valve and you get permanent loss of electrolyte when they vent. Some AGM's do this above 14.2 volts , others do it above 14.4. What ever the max charge voltage of your AGM... you would be better served by a flooded battery unless you get a very high quality solar control that also (probably MUST have in your situation) a remote temperature sensor that you place on the AGM battery. Manufacturers that have this include some models in the following high quality companies:  VICTRON, SCHNIEDER - XANTREX, MORNINGSTAR, MIDNIGHT, and others.  Many of these will not have "remote" temperature sensors and instead will have 'internal' temperature sensors. The internal sensors would be the bare minimum to consider and that is predicated on the charge controller (c/c) being in a location with the same temperature (during the daytime) as the battery. Batteries under charge heat up a bit (or allot under a high charge i.e. >15% capacity);  so it is better to use a remote sensor when/if you can make the economic justification or when charge rates are high.  In your situation with a 20 watt solar module and a 75 Ahr battery... you should be fine with internal temp comp and a PWM style charge control with reliable 3-stage charging like the MorningStar SS-6-12V https://www.morningstarcorp.com/wp-content/uploads/2014/02/SunSaverENG_R3_5_12web1.pdf 

I run: VHF, small depth sounder, 2 small LED lights, small hand held GPS, 2 phones to charge, nav lights (hardly as we don't navigate at night). Maybe plan to install a stereo at some stage...

You may wish to consider the larger battery, a larger c/c, for this type of load if you are regular user of the boat and wish to have solar power on the hook as opposed to only for day sails.

Thanks.

 

See my comments in your text above....