My Battery Pholosophy
Someone asked: What I need to know now is what standard american batteries have some of you folks used? In other words what will fit, and provide the cranking amps needed required.
Hi Guys, I'm new here and I realize this post is fairly old but the topic is of interest to me and I don't see anyone saying what I'm about to say so... here goes.
I worked for over 12 years in the "old school" auto parts industry and there is some info I picked up about batteries that I think bears repeating.
Lead/Acid batteries have lead plates that stand in sulphuric acid and the chemical reaction between the two produces electrical current. The amount of surface area of the lead plates that is exposed to the acid determines how quickly the chemical reaction can take place. Also the thickness of the lead plates determines how much capacity the battery has to "hold" a charge.
You may have noticed that batteries have two different numbering systems that are designed to give you an idea of how the battery performs. The first, and most quoted, number is CCA (Cold Cranking Amperage). In simple terms this is how many amps the battery is designed to "pump" out when the battery is cold or how quickly the power in the battery can be jolted into the system. To acheive higher CCA the manufacturer will try to increase the surface area of the lead plates inside the battery. To keep the battery the same size so it will still go in the dozer they have to make the lead plates much thinner and put more of them in. But this also DECREASES the amount of lead in the battery so it DECREASES the Length of time that the battery can put out that kind of amps.
This "length of time" is what the other number on the battery stands for and it is called "Reserve Capacity".
What this translates to in real life is you can have a battery with high CCA that turns the engine over FAST or you can have a battery with high Reserve Capacity that (when it is cold) will turn over more slowly but will turn over much longer (or run the lights much longer). You can't have BOTH unless you go with a bigger battery which may not fit.
My experience through the years has unfailingly indicated that I do not need high cranking amps as much as I need high reserve capacity.
So I have chosen for at least 25 years to opt for Deep Cycle Marine Batteries on all of my equipment and autos. When the temp drops to zero they crank slower but MUCH longer. (This is helpful on a cold diesel.)
My lights were accidentally left on at work (in my pickup) for over 4 hours and the battery cranked it as though they hadn't been left on.
Specifically on my D20A-5 I am running two 24DCM batteries from the local auto parts (that stands for group 24 Deep Cycle Marine). They are a bit more pricey than "normal" batteries but much less than OEM, and they WORK GREAT. Put the DCM next to a normal battery of the same size and heft them... you'll immediately feel the difference in "Reserve Capacity". The DCM is noticably heavier. They are a snug fit but mine have worked very well for years.
Best Wishes,
Richard
