Golf Car BATTERIES at SAMS?

Re: Golf Car BATTERIES at SAMS?

I have had 3 customers use them and they where half the cost of the ones i use. so far they seem to work ok but i worry they are doing something to cut the cost. i have not tested capacity but it feels like to me they dont have the capacity they claim they do.

Re: Golf Car BATTERIES at SAMS?

I will qualify my post by saying that my experience with GCB is 26 years old, but I do not think much has changed.

I would suggest you do some deep research of golf cart batteries (GCB) if you are planning on using an inverter.

I was told not to use them, that they would not last. Like advice from my father, I ignored it, seems we always have to learn for ourselves.

Batteries are engineered for a particular use, and GCB are designed to give up the necessary power that is needed for the cart, no more no less, and this is a known load range, unlike what you are going to be drawing with an inverter.. Inverter loads can momentarily hit 600 amps, with out any trouble, and you can not see it on a Fluke amp meter, it is not quick enough, I have personally seen it run up to 470 Amps, before the load display disappeared.

My point is you will go through many different battery setups before you finally realize you are wasting money. At the very least I would get Trojan L 16s these will give you 4/5 years of reliable service.
One of best is the Surette Rolls Royce brand, but they are not cheap and neither is your time and material for setting up the bank. If you are in a planning stage, allow plenty of room to expand the battery bank in the future.

Re: Golf Car BATTERIES at SAMS?

I think some of the comments about current and battery life are why 48 volt systems are far superior to 12 volt systems. My old fridge had a 30A @ 120VAC inrush current. That's 300A @ 12V plus conversion losses. At 48VDC it's much more manageable.

Re: Golf Car BATTERIES at SAMS?

Photowhit wrote: »

I, on the other hand, am from coastal Florida, where L16's are a boat battery. Which made for some short term confusion when I first came to Solar Forums, about boat batteries not being real deep cycle!

I don't believe that anyone ever said that "boat" batteries were not deep cycle. What has been said, and what have said for many years is that "marine" batteries quite often (nearly always) not deep cycle.

"Marine" is a marketing term, deep cycle is a technical term.

Re: Golf Car BATTERIES at SAMS?

Cariboocoot wrote: »

30A @ 120 VAC?! My 1 HP sump pump doesn't do that!
There must have been something wrong with it. Good thing you got rid of it. What a monster!

Are you sure your pump doesn't? Assuming perfect efficiency, that 1HP pump is 755 watts at whatever voltage you're using. Of course, it isn't perfectly efficient, and assuming a power factor of .7, apparent power is likely WAY higher than 755 watts (755 / .7 = about 1100VA), while running, making it even easier to reach that 30A figure.

Since inrush and locked rotor current tend to be moderately close instantaneously, I'm betting you are seeing something close to 3.6KW momentarily, unless you have a slow start setup or are using 3-phase. Put a scope or recording meter on the circuit -- you might just be surprised.

Re: Golf Car BATTERIES at SAMS?

I bought golf cart batteries at BJ's Wholesale Club. These were Exide GC-135 batteries. Cost at the time was $79. Rated at 6V, 226 AH (20 hr rate).

The batteries were fresh (dates right on the batteries), and have been in use a couple of years. They are doing very well, and I periodically measure the specific gravity to verify this.





Got six of them so far. My local supplier still carries this brand, but a lower capacity model. Going to pester them soon to see if I can still get the larger model.

As for in rush current, this is HARD to measure. Most ammeters are not quick enough to capture the peak. I bought a Fluke model 334 meter for this specific feature.



My 5000 BTU window shaker pulls 22.6 Amps to start, then under 5 Amps to run.

My Dewalt Emglo 120VAC air compressor (air tank drained), pulls 53.8 Amps:



The 13,500 BTU A/C unit on my travel trailer pulls 50.5 Amps starting, 10.5 Amps running.

I haven't tested my refrigerators yet, but that's coming. Curious to see how my numbers compare.

Re: Golf Car BATTERIES at SAMS?

We need Myth Busters to test every battery available to see which one is the best battery for each application.

Anybody have a Myth Buster login?

Re: Golf Car BATTERIES at SAMS?

RC,

That was an excellent description of LA battery chemistry. I particularly liked the cut/healing/scaring analogy.

No myth here to be "busted."

Re: Golf Car BATTERIES at SAMS?

re "Short definition for deep cycle is thick plates." - what you are saying is that there is no definition for "deep cycle" that is worth a hoot as far as anything measurable. There is nothing that marks a boundary between deep cycle and not deep cycle or between deep cycle and true deep cycle. That means that, as many use the term. it is meaningless or even misleading.

From the description it suggests that you should be able to tell how much emphasis a battery places on the 'deep cycle' corner of the trade-off triangle by looking at energy density by weight. The last time I took Trojan's line card and put it into a spreadsheet, such a distinction was not there. The differences in energy weight density were insignificant when compared to other influences on battery energy capacity.

What that tells me is that modern lead acid battery manufacturing is a mature technology and rather well optimized. The need to expose lead to acid for maximum capacity, obtaining a proper strength in the plates to avoid failure due to shock or corrosion, and the 'tuning' of the chemical reaction to avoid undesired outcomes such as gassing are reasonably well understood and techniques defined. There really isn't a whole lot of variance from one end of what is reasonable (and cost effective) to the other in tuning the parameters for a particular need. (with due caveat to the context)

To me this is why the FAQ suffers a bit in coherence. The measures it cites do not fit well with the generalizations it emphasizes on this issue. (then go see the RV page to really get confused!)

If you are looking for hard numbers about what deep cycle represents, it also appears to me that you are bound to be disappointed. There must be a reason why measures for 'deep cycleness' are not readily available; why you don't see cycle ratings in common spec sheets; why warranties have more to do with how a battery is likely to be used than with the battery itself.

From what I can tell, battery life is most significantly influenced by usage and maintenance management. The factors that are involved are well known. Yes, you do need to select batteries that are built for the job you intend to do but the talk about deep cycle as if there are "true" varieties and 'false' ones doesn't help anyone IMHO.

I think we'd do a lot better in battery discussions if we separated conceptual things like deep cycle from measurable things. The conceptual things are nice to get a handle on understanding what we are talking about. The measurable things we need in order to design our systems and make effective choices. When the two overlap, we get into misperceptions about precision and accuracy and weighting of variables that tend towards poor decision making.

Re: Golf Car BATTERIES at SAMS?

bryanl wrote: »

If you are looking for hard numbers about what deep cycle represents, it also appears to me that you are bound to be disappointed. There must be a reason why measures for 'deep cycleness' are not readily available; why you don't see cycle ratings in common spec sheets; why warranties have more to do with how a battery is likely to be used than with the battery itself.

Most deep cycle batteries on this side of the bond are rated according to specific IEC, EN or DIN standards. Standard EN/IEC 60896-21 for example, tells you how many cycles of 80% DoD to expect. Most OPzS or PzS traction batteries will state this in their spec sheets.

Here's a discussion of the testing procedures for that standard.

Re: Golf Car BATTERIES at SAMS?

re "Look at the specs they're willing to give:" - not much different from any other line card I've seen and nothing near the Giess paper idea. The only measure for life (what deep cycle is all about) is the warranty. There are sufficient capacity measures to determine a Peukert coefficient but you can also get that from the 20 hour and 25 amp measures normally provided with any battery. I need to see if I can find my spec spreadsheet so I can calculate weight energy density for these but the range appears to be about the same. The warranty is what tells you the 'deep cycle' story (as well as the expected use story).

re "Everytime I look at the 25PS series positive plate thickness" - this sounds like a 50's car enthusiast commenting on the tail fins ... ;-)

re "not being up to RE capability" - is there a good definition for this? I assume it is talking about a load or use profile. Where I stumble in any lead acid battery energy storage is trying to balance diurnal cycles with necessary charge times with the known drop-off in life expectancy from 50% SoC to 20% and with the drop off in life expectancy in float service. Then there is the problem of trying to classify energy draw peak and average compared to bank impedance and battery design. - from Surrette's warranty, it appears that the expected RE use profile is a daily discharge to about 75% SoC at less than the 20 hour rated energy draw with prompt charging and a narrow distribution.

Re: Golf Car BATTERIES at SAMS?

The data sheet for my East Penn 8AGC2's does have a bar graph showing number of cycles for different DoD.

http://www.visi.com/~ch3dietz/solar/8AGC2.pdf

Also note that they don't call it deep cycle.