Have my batteries reached the end?!

[Mrtoast]

So here is the story - I bought a couple of solar panels last october and had a great experience with them. Foolishly i went with the advise that I wouldn't need a controller. Well that was great until the really hot days over the past weeks or so. I started to worry first thing in the morning and check the batteries with a multimeter and most days they was in the 13.8 - 14.8 and one or maybe two times it reached 16v. I always put load on the batteries whilst the sun was out and covered over the panels just incase - Keeping them in the 13v region. However, I have since discovered when they get to around 12.6v they drop off really low into 11v FAST! - in which case i turn everything off and they creep back to full charge. (this has only started to happen last couple of days).

 

I have borrowed a sulphating charger and it seems to be charging fine at the moment. Just wondering if anyone has had any similar experience?

 

And yes i now have a controller but maybe a little too late.

 

1 Starter

2 x 110 LB's Sealed

2 x 100w Solar Panels

 

Cheers

Chris

[Grace and Favour]

Although I'm no expert - I would agree, and think your batteries are toast.

[by'eck]

The voltage you are measuring is generally the charge voltage, i.e. the voltage the solar output current takes the batteries to. From the sound of it as soon as this charge current is taken away, the batteries having virtually no capacity left have their voltage dragged down very quickly by whatever load you have on them.

 

The fact that their voltage recovers when the load is removed is entirely normal and due to surface discharge effect, but still leaves you with batteries of low capacity, which will probably need replacement.

 

Its possible that if they are open cell lead/acid you can perform an equalisation cycle on them with suitable mains charger to de-sulphate and so restore them to some degree, but I wouldn't hold your breath.

Edited July 16, 2014 by by'eck

[Mrtoast]

The voltage you are measuring is generally the charge voltage, i.e. the voltage the solar output current takes the batteries to. From the sound of it as soon as this charge current is taken away, the batteries having virtually no capacity left have their voltage dragged down very quickly by whatever load you have on them.

 

The fact that their voltage recovers when the load is removed is entirely normal and due to surface discharge effect, but still leaves you with batteries of low capacity, which will probably need replacement.

 

Its possible that if they are open cell lead/acid you can perform an equalisation cycle on them with suitable mains charger to de-sulphate and so restore them to some degree, but I wouldn't hold your breath.

 

Yeah im grasping at straws really and if i can get a couple of weeks out of them then great. You'll have to forgive me but if my batteries are sealed and i have them on a charge now. They have been on for about 8 hours still charging and reading 14.3v. Is this fine to let the charger to kick into ready and maintaining mode? I wouldn't want them to blow up or anything.

[Mrtoast]

Charged! See how one responds tomorrow. Cheers for the advice.

[Paul C]

Have you checked the eletrolyte level recently? The overcharging might have boiled the electrolyte to a dangerously low level and knackered them that way.

 

Do you have any idea of what the state of charge of the batteries, actually is? (For this you'd need a smartgauge, or an amp-hour counter, or simply know what the solar panels have done recently vs the power consumed, which isn't as simple as it sounds and involves guesswork).

[blackrose]

Have you checked the eletrolyte level recently?

 

 

1 Starter

2 x 110 LB's Sealed

 

 

I suppose his start battery might be wet lead-acid?

Edited July 17, 2014 by blackrose

[Paul C]

Probably all the more reason for checking it then! A sealed battery isnt completely sealed, it will be valve r egulated (the VR in VRLA). And once its gone ,, almost impossible to top up

[smileypete]

A lot of the sealed leisures are 'sealed for life' flooded calcuim batts with no means to routinely top them up.

 

But often they have some sort of filling plugs for initial filling and these can sometimes be removed for checking and so on, by someone careful and suitably competent. I definitely wouldn't recommend anyone just attack a duff sealed leisure batt any old how, on the off chance they can save it!

 

cheers, Pete.

~smpt~

Edited July 19, 2014 by smileypete