what does 125 RC mean on a battery

System

I understand cranking amps and amp hours, but some Power Volt Maximum Deep Cycle Batteries were offered to me and they have this and only this stamped on them. The company said Texas but made in Mexico
Bill

BB.

Re: what does 125 RC mean on a battery

From here, RC means:

Reserve Capacity, (RC) is a battery industry rating, defining a battery's ability to power a vehicle with an inoperative alternator or fan belt. The rating is the number of minutes a battery at 80 degrees F can be discharged at 25 amps and maintain a voltage of 10.5 volts for a 12 volt battery. The higher the reserve rating, the longer your vehicle can operate should your alternator or fan belt fail.

In general, automotive batteries are not good deep cycle storage batteries... If you can keep them cycling from 100% to 85% State Of Charge (use 15% or less of their capacity), then they might be OK as they are free and you have a place to properly recycle them without much cost to you...

Otherwise, if these are really deep cycle batteries then the 2 hour Amp*Hour rating for those batteries would be:

125 min * 25 amps / 60 min = 260 amp*hour

The 20 hour rate (which is usually more representative of how we would use batteries in a typical solar system) would be somewhat higher.

-Bill

System2

Re: what does 125 RC mean on a battery

Thank you, the only other ledgible marking on the battery is V24DC6 Does this indicate that they are true deep cycle batteries
bill

BB.

Re: what does 125 RC mean on a battery

Looks like it may be a marine battery?

From our host's Battery FAQ:

• Starting (sometimes called SLI, for starting, lighting, ignition) batteries are commonly used to start and run engines. Engine starters need a very large starting current for a very short time. Starting batteries have a large number of thin plates for maximum surface area. The plates are composed of a Lead "sponge", similar in appearance to a very fine foam sponge. This gives a very large surface area, but if deep cycled, this sponge will quickly be consumed and fall to the bottom of the cells. Automotive batteries will generally fail after 30-150 deep cycles if deep cycled, while they may last for thousands of cycles in normal starting use (2-5% discharge).
• Deep cycle batteries are designed to be discharged down as much as 80% time after time, and have much thicker plates. The major difference between a true deep cycle battery and others is that the plates are SOLID Lead plates - not sponge. This gives less surface area, thus less "instant" power like starting batteries need.
• Unfortunately, it is often impossible to tell what you are really buying in some of the discount stores or places that specialize in automotive batteries. The golf car battery is quite popular for small systems and RV's. The problem is that "golf car" refers to a size of battery (commonly called GC-2, or T-105), not the type or construction - so the quality and construction of a golf car battery can vary considerably - ranging from the cheap off brand with thin plates up the true deep cycle brands, such as Crown, Deka, Trojan, etc. In general, you get what you pay for.
• Marine batteries are usually actually a "hybrid", and fall between the starting and deep-cycle batteries,though a few (Rolls-Surrette and Concorde, for example) are true deep cycle. In the hybrid, the plates may be composed of Lead sponge, but it is coarser and heavier than that used in starting batteries. It is often hard to tell what you are getting in a "marine" battery, but most are a hybrid. "Hybrid" types should not be discharged more than 50%. Starting batteries are usually rated at "CCA", or cold cranking amps, or "MCA", Marine cranking amps - the same as "CA". Any battery with the capacity shown in CA or MCA may not be a true deep-cycle battery. It is sometimes hard to tell, as the term deep cycle is sometimes overused. CA and MCA ratings are at 32 degrees F, while CCA is at zero degree F. Unfortunately, the only positive way to tell with some batteries is to buy one and cut it open - not much of an option.

-Bill