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Re: another battery question
Posted: 10 Nov 2009, 15:02
by Cafnod
Eta-Beta wrote:Get a gell battery,, much better
Can you explain why a gell battery is better please?
Re: another battery question
Posted: 10 Nov 2009, 16:37
by kevtherev
Gel, is a standard lead acid battery except that the acid has been transformed into gel. But by solidifying the electrolyte, you introduce many problems not associated with free flowing water based batteries.
The question is, better at what aspect?
maintenance-free? no such thing , all batteries are basically the same. A Gel, sealed lead acid and AGM are all only maintenance-free because of the
reduced charging performance curves; and not because there is something special about the battery. If you charge a normal lead acid battery to the Gel or AGM curves, then they would not require maintenance either.
Remember 'maintenance free' is a handicap to fast charging not an advantage. This feature, which on the surface looks good, is, in most cases the worst feature that you could possibly buy; as this feature dramatically limits the maximum charging characteristics of the battery.
Fast charging costs water, i.e. if you want to charge you batteries fast, don't touch a Sealed/Gel/AGM etc with a barge pole. Fast charging will result in a certain % water loss from the battery. If the battery is
sealed the water loss cannot be replaced.
alternators are fast charging
gel batteries are expensive,
best ever, ever, ever, Leisure batteries are
traction batteries.
*gets off soap box*

Re: another battery question
Posted: 10 Nov 2009, 17:00
by Cafnod
Hi Kev
So gel or AGM batteries arent any better?
And they are not suitable for alternator charging without a constant voltage device with a built in current limiter without which their life is going to be shortened because they cannot take the number of fast charging cycles a conventional battery can?
No mention of the pressure relief valve that can open if they are not charged properly and vent battery acid everywhere.
But you can mount gel batteries upside down.
However you cant charge them upside down.
And even though they give off gas, admittedly in limited quantities, (unless the pressure relief valve opens), its not possible to top them up.
So if I understand what you are saying Kev these batteries are only any use if you charge them with a dedicated charger or a via specialist external alternator regulator?
Oh dear so why the big glossy adverts saying how wonderful they are?
It couldnt be that the capitalists are lying to us again could it?
Re: another battery question
Posted: 10 Nov 2009, 17:21
by CovKid
Not sure politics comes into it but marketing certainly. I guess there are two ways of approaching this, looking for greater capacity batteries or sinking your money into low-energy gadgetry. High capacity energy storage in conjunction with improved energy capture (and I gather they've developed solar glass now) is another route but tadge expensive.
Re: another battery question
Posted: 10 Nov 2009, 17:46
by kevtherev
Cafnod wrote:
It couldnt be that the capitalists are lying to us again could it?
yes.. I guess some people are just plain gullible..
Re: another battery question
Posted: 10 Nov 2009, 17:55
by Cafnod
Seen these things in the marine world. Gin palaces have them. Funny the real yachties seem to go for £5 batteries from the scrappies unless they are doing a circumnavigation or something equally arduous.
I agree with Kev on tractions, I had the option of two pallets of fork lift batteries and an industrial charger a few years back, couldnt find anyone interested in any, I wanted about half a pallet for the n/boat but had to be all or nothing.
Re: another battery question
Posted: 10 Nov 2009, 19:29
by CovKid
I presume you've all seen the electric T25?
http://www.youtube.com/watch?v=8ybosDWzD3I" onclick="window.open(this.href);return false;

Re: another battery question
Posted: 11 Nov 2009, 18:11
by Fozzie
Cafnod wrote:Cannot seem to paste images into posts
Not sure you ever got a reply to this, so if you're still wondering:
Go to "Post a Reply" as normal, and type your text. Notice the two tabs (underlined red on pic) underneath the text box, marked:
--> "Options" (where "Disable BBCode" should NOT be ticked); and
--> "Upload Attachment" - click that, then browse for your image and "Add the file"
hints.jpg
Once uploaded you then have the option to place the uploaded image inline in your text.
Apologies for polysyllabic response, but hope you get the idea...
Re: another battery question
Posted: 11 Nov 2009, 18:49
by Cafnod
Excellent Jim, thanks a bunch or that.
Re: another battery question
Posted: 11 Nov 2009, 18:54
by CovKid
You can do it there but its only temporary for that post. Better to go to user control panel (above) and board preferences as I said earlier.