Boxing Clever

[Leicester Fisheagle]

A few weeks ago I started to have problems with my plotter and radio and started to get a low voltage alarm. I thought it was simply short runs, use of bait pump etc. and that since the problem had been gradual in coming that a quick voltage check both batteries was needed.The main batter without anything running gave just under 13 volts and the service battery 11.4 volts. A charger check with the engine running gave a charging rate of 14.2 volts to each battery so all seemed OK on the charging side..

 

A charge to the service battery would only put in just over 12.8 volts so I was suspicious that there was a battery problem, perhaps a duff cell. I then asked Dave (Coddy) to bring his state of the art charger and tester, He confirmed that the battery -showing 11.2 volts and rapidly dropping to 9 - had died. Indeed, a further test showed it had about 100th. of the cranking power of the main battery,

 

So far. we had been able to test and recharge the batteries in situ, but it was now time to take out the service battery and battery box from its recess.

 

The battery had cracked and the bottom of the battery box was full of electrolite/sulphuric acid. The new battery, replaced under warranty appears fine.

 

This is the third battery that has done this to me in 40 plus years, but the first on a boat. Had it not been in a battery box, i dread to think of the possible damage. How often have we seen batteries on boats without boxes?

 

Allan.

[great white]

Thanks for sharing your warning Allan

 

Any idea why the battery split?

[Leicester Fisheagle]

No Charlie, nothing overtight, no signs of overcharging or heating up. Maybe Nigel can tell us if it happens from time to time. Worked fine for 6 weeks. Don't know if damaged when fitted. Bit of a mystery, but not funny if you only have one battery. Makes a good case for a spare with rotary switch if practical.

 

Allan.

[PaulRaider18]

Thinks I will check both battery's and boxes very soon, cos when you think about it, we got both mounted aft and they take a fair bit of rock and roll, very good point cheers

[Mike Fox]

Perhaps they weren't strapped down tightly enough, and the pounding at high speeds (anything above 6 knots in my case) might have caused them to move and bounce within the boxes?

 

It's a scary thought having loose acid in the hull, with seacocks, anode bolts etc straight through to seawater. Glad you found it early!

 

Frisky has 2 domestic batteries (11-12 years old but getting tired) and 1 cranking battery (second season), all 110 amp hour and about 12.8v at rest, with switching available. I don't have boxes, but have all batteries strapped down tight to the hull webbing, in the event of a knockdown. I do like the idea of boxes, and will investigate if they might fit!

 

Mike

[Leicester Fisheagle]

Mike

The boxes cannot move forward or side ways and are well strapped down, However, the batteries could move within the box. vertical movement would be restricted slightly by the cables but, as you suggest, there could be some lateral movement. Would some inert substance like polystyrene work underneath and around the sides of the battery or could that cause heat build up? If it is movement, it is probably up/down so something to cushion underneath? Wiill enquire what power boats do. Suggestions/help appreciated,.

 

Allan.

[niggle]

Not heard of batteries splitting

Possible causes:-cheap batteries?

Sediment shorting out plates when shook about

Sea water splashing over battery terminals?

 

Probably none of above but only cause I can think of

[Leicester Fisheagle]

Thanks Nige

They were Factory fitted Exides, but where they were made I don't know. Batteries well protect and dry.New batteries so shouldn' be sediment so as you say, possibly none of above. 

 

Allan.

[great white]

In my experiance it is best to ensure that the batteries can not move within the boxes.

 

Mine are standing on non slip rubber matting, with rubber blocks stopping them sliding around in the box

 

Charlie

[Rob]

Wooden wedge for me!

[Steve S]

As it's a pretty new battery it most likely was a manufacturing defect.

 

All the above advice on securing the battery to reduce movement and having it in a box (without holes) all good sense, using rubber as Charlie does help reduce vibration to the battery which is helpful as well.

 

I always buy quality flooded cell types as they take a lot more abuse and are low cost relative to other technologies, however, acid leaks can be an issue and also remembering to check the fluid levels.

 

Steve