Loyalhanna Dockyard & Taubman Plans
7527 Gilbert Road Bergen, N.Y. 14416-9768 Tel: 585-494-0027 Fax: 585-494-1369
December - 2004
BATTERY CHARGING – LEAD ACID
I was asked recently to do a presentation on Battery Charging for one of our local clubs, so I thought that I would present that information here as well. As each Battery Chemistry has different charging requirements, let’s take a look at the lead acids first. The other types will be covered in subsequent newsletters.
The lead acid batteries we use in our models are really no different than the Battery in our car. The Chemical properties and reactions are the same with the only real difference being the form of the Electrolyte . The Electrolyte in our hobby batteries has been produced as a Gel (Hence the term “Gel Cell”). The Gel Electrolyte allows the battery to be mounted in any position without the worry of leaking. A great advantage for our models as this allows us to mount the battery in any position needed to make the most of the space available in a hull. The drawback is the gelled electrolyte batteries are more sensitive to an over charge. Therefore, let’s take a look at the proper way to charge a “Gel Cell” battery. These batteries need to be charged at a constant voltage of 2.3 to 2.4 V per Cell. When charging at this fixed voltage, you will notice that the charge current will vary. The current will be the highest when you first start to charge the battery and will slowly decrease as the battery reaches full charge. Eventually, the charge current will drop to zero and the battery will be considered fully charged. The beautiful thing about this whole process is that as long as you are using the proper charger, you will never overcharge the battery. If you would like help selecting the proper battery charger for your needs, please feel free to contact us for recommendations. Also, please keep one more fact about lead acid batteries in mind. The easiest way to ruin them is to let them sit for long periods of time in a discharged state. Since we obviously don’t want to waste the money we have invested, and since these batteries can’t be overcharged, the best course of action is to charge them once every four (4) weeks when not in use. (i.e. winter storage). Of course, this goes without saying that the batteries should also be charged when returning home from a days run.
Next month we will take a look at NICAD/NIMH Batteries.