Numax Battery

[silverdawn]

Hi All, End of season I removed battery from boat and brought home to charge, duly charged it reached 12.6 volts after 6 weeks it had discharged to 12.3 volts so I trickle charged it back up 12.6 and left it again for 6 weeks , 3 days ago it showed 11.8 volt! but the charge window is showing green as fully charged ?. I tried to recharge it but although it charging at 13.4 volts it has fallen back down to 11.8 but the green fully charged light still shows.
The multimeter and the charger are okay both have been checked by using alternative ones, the battery is a Numax maintenance free 85Ah.
it has 04/05/06 on the top so could be new from any of these dates so quite old, I suspect its had it day but why does the green light show okay any advice gratefully received prior to me spending £85/95 from ever decreasing boat budget.
regards Stuart.

 

[VicS]

The green indicator is only showing that the acid density is OK in one cell. You may have one or more dead cells


Get it on a more powerful charger... one that will charge it at 8 or 10 amps and preferably one with a "reconditioning " stage. It may respond , it may not.

 

[Zagato]

Halfrauds will also check it for you for free

 

[Talulah]

Halfrauds will also check it for you for free

I understand from another forumite who recently went to Halfords found it to be no longer the case.
Can't remember the excuse now.

 

[Stemar]

Halfrauds will also check it for you for free

Then tell you it's faulty (whether or not is is) and charge you twice as much as you'd pay elsewhere for a new Numax for a rubbish own brand one.

 

[Spyro]

Yes is sounds like it has had it. Numax 85 ah batteries on Ebay are a lot cheaper that £85/95. I just bought a new 100ah for £65 inc postage.
I was also surprised when I took 2 old ones to a local scrap/recycling center that they give you 40p per Kg for lead acid batteries.

 

[silverdawn]

Thanks for all the replies, will try another charge then take the battery to supplier to test, thanks for the info on the green charge indicator. regards Stuart.QUOTE=VicS;4064457]The green indicator is only showing that the acid density is OK in one cell. You may have one or more dead cells


Get it on a more powerful charger... one that will charge it at 8 or 10 amps and preferably one with a "reconditioning " stage. It may respond , it may not.[/QUOTE]

 

[Plevier]

The high rate discharge testers used by garages, Halfrauds etc won't really tell you much about the capacity of a "house" battery, they are intended for vehicle SLI batteries. (Jargon - starter, lights, ignition)

 

[Talulah]

The high rate discharge testers used by garages, Halfrauds etc won't really tell you much about the capacity of a "house" battery, they are intended for vehicle SLI batteries. (Jargon - starter, lights, ignition)

Isn't is called a 'drop test'? Halfords stopped doing them. Maybe staff misunderstood.

 

[Plevier]

Isn't is called a 'drop test'? Halfords stopped doing them. Maybe staff misunderstood.

Hadn't thought of that. Need a nice ROFL smiley. These new ones are a downgrade aren't they!

 

[VicS]

Hadn't thought of that. Need a nice ROFL smiley. These new ones are a downgrade aren't they!

I still have the one everyone hated when it was available........