To leave battery on charge on not

[ylop]

Rest of boat should be ok in a barn.

So is the panel o/side the barn? Because even if the barn has no sides I can’t see any panel generating enough power to be a concern if it’s shaded by a roof.

Solar panel is large ish; cannot remember wattage but it must be about 3 foot long by 1 foot wide (very approx from memory)

So maybe a 50-60W panel, probably not optimal position for sunlight for most of the day probably now quite grubby, I wouldn’t worry about it!

Previously I thought batteries left even with no drain would diminish over time.

Typically they do. The rate of discharge depends on type of battery, temperature etc. often suggested 5% per month. So if your batteries had been left for 30 months they potentially would be dead.

 

[Zing]

I have just realised I have a boat (better to call it a project) that I have not been near for just over 2 years. It is stored a LONG way away from me.

I have left a large (in size, cannot remember capacity) battery (open lead acid) on a solar panel all that time via a controller (told it was MTTP) but suspect it is not and is a cheap old thing.

Have read a post where Vyv-Cox left a battery without charging for 3 years and it was ok.

Have I done wrong?

Should I visit or try to find someone to disconnect the solar panel and check the distilled water levels are ok?

Or is it too late (such batteries are comparatively cheap) and just save a lot of petrol and hassle and leave the thing?

If you read battery manuals (as I enjoy doing) you will quickly see that you should float charge your lead battery to prolong its life. It will die quicker if you don’t do that. Lithium is the opposite rule BTW.

RTFM.

 

[Snowgoose-1]

Interesting thread.

Would a " Smart" charger deal with potential over charging ?

I ask because I have a car battery connected to 240v left on charge using a "Smart".

I never seem to have a problem on the boat with solar power overcharging.

 

[vyv_cox]

According to many posts I have read on a variety of forums, there is no problem with constant solar charging unless a cell goes down in the battery. This not unusual due to sulphate falling off the plates and bridging the cell. The regulator then sees the battery voltage low and boosts the charge to compensate. The result can be overheating, melting and fire.

 

[Snowgoose-1]

According to many posts I have read on a variety of forums, there is no problem with constant solar charging unless a cell goes down in the battery. This not unusual due to sulphate falling off the plates and bridging the cell. The regulator then sees the battery voltage low and boosts the charge to compensate. The result can be overheating, melting and fire.

Good point about overcharging due to cell failure. If in a marina or hard standing, there is good chance that a smoke alarm might be heard.

 

[PaulRainbow]

Good point about overcharging due to cell failure. If in a marina or hard standing, there is good chance that a smoke alarm might be heard.

Not usually any smoke to set a smoke alarm off. Very often enough hydrogen to set a Co alarm off though.

 

[wonkywinch]

Not usually any smoke set a smoke alarm off. Very often enough hydrogen to set a Co alarm off though.

MDL called me a few times about CO alarm sounding. I found out it must have been the batteries gassing. Discovered the Cristec charger DIP switch set to AGM though batteries basic lead acid.

Changed DIP switch, batteries charge OK, no alarms.

Now I generally switch everything off and only leave the charger on for a few days each fortnight.

 

[Alex_Blackwood]

I have just realised I have a boat (better to call it a project) that I have not been near for just over 2 years. It is stored a LONG way away from me.

I have left a large (in size, cannot remember capacity) battery (open lead acid) on a solar panel all that time via a controller (told it was MTTP) but suspect it is not and is a cheap old thing.

Have read a post where Vyv-Cox left a battery without charging for 3 years and it was ok.

Have I done wrong?

Should I visit or try to find someone to disconnect the solar panel and check the distilled water levels are ok?

Or is it too late (such batteries are comparatively cheap) and just save a lot of petrol and hassle and leave the thing?

I should take some of this with you, you may need it
https://www.amazon.co.uk/Carplan-io...lpcontext&ref_=fplfs&smid=A3P5ROKL5A1OLE&th=1
Seriously I think that you are the only person who can answer your question, when you see the battery. I would suspect that irrespective of anything else the electrolyte level will be low and need topping up, possible a lot.

 

[Cerebus]

Thanks for replies.

 

[jakew009]

.

 

[thinwater]

... Rest of boat should be ok in a barn.

The solar is turned off. No sun.

In fact, the charging system may actually be draining the battery, depending how dark it is. The controller will use ~ 10-30 mA (1-2 Ah per week). There are likely other parasitic loads on the boat (powered-down electronics that still draw some mA even when off).

The safe bet was to charge the battery and then take the cables off.

 

[Cerebus]

The solar is turned off. No sun.

In fact, the charging system may actually be draining the battery, depending how dark it is. The controller will use ~ 10-30 mA (1-2 Ah per week). There are likely other parasitic loads on the boat (powered-down electronics that still draw some mA even when off).

The safe bet was to charge the battery and then take the cables off.

I placed the solar panel on roof of barn.