Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Batteries & Chargers => Topic started by: Koldness on December 16, 2006, 10:02:07 pm

Title: How to: Gel Cells?
Post by: Koldness on December 16, 2006, 10:02:07 pm

Hi all,

     Can some of you offer some input into gel cells, I have a small 6 volt graupner motor powered TID, I would like to use a small gel cell.  What should I get and how and what should I charge it with?

thanks

Kris

Title: Re: How to: Gel Cells?
Post by: Stavros on December 16, 2006, 11:29:12 pm

First question is how much room have you got,easy measure your room go down to Maplins with tape measure but also buy a dedicated charger from Maplins as well.Hope this is of some help.By teh way is your Tid a kit or self built and how long is it

Title: Re: How to: Gel Cells?
Post by: Koldness on December 16, 2006, 11:33:35 pm

Ha you will chuckle!  Its my first build, a Lesro TID.  its about 22 inches long.  I have found some very small Gel Cells at a few electronics stores.  Charging is my issue, what is special about gel cell charging?

Title: Re: How to: Gel Cells?
Post by: Stavros on December 16, 2006, 11:43:01 pm

Hi it is all down to the amount of AMPS that the chargers give out.I use 12v gell cells but if i charged them with say a Halfords car charger I would xxxx it up.Simple reason for htis is that most gell cells only require so I have been told a maximum of 500ma to charge,so charging with an ordinary 12v car charger giving off 7amps would absolutely  fry the batt.Hope this is of help,try searching teh site for batt charging and gell cells for more info good luck  Stavros

Title: Re: How to: Gel Cells?
Post by: Scottie on December 16, 2006, 11:56:04 pm

Stavros has said it all - get a dedicated gel-cell charger. The only thing I would add is that it's worth paying a little extra and getting one that can switch between 6 and 12 volts. That way you won't have to buy another if you ever get a 12 volt battery. Just about every model shop carry them.

Scottie

Title: Re: How to: Gel Cells?
Post by: John - ModelPower on December 17, 2006, 12:06:13 am

Hi All
       Check our web site @ modelpower.co.uk we have the charger you require and a good range of gel cell.
              and cheaper than maplin!!!!!!!!!!!!

                                                    John Modelpower.co.uk.

Title: Re: How to: Gel Cells?
Post by: roycv on December 17, 2006, 04:24:41 pm

Hi getting a dedicated charger is good advice.
Gel cells (lead acid) are best charged by taper charging.  This is applying a fixed voltage equal to the final fully charged voltage of the battery.
The current can be limited but as the battery voltage rises (charges) up to meet its full voltage, so the current gets smaller or 'tapers off'.
At the moment metal  hydride cells offer a very good power to volume advantage.  I would think that for a small space you might be better off with these.
regards Roy

Title: Re: How to: Gel Cells?
Post by: Stavros on December 17, 2006, 05:11:18 pm

john quite right as well cos I got one ond flippin marvelous excellent as well