minimum CCA's needed

[dudedude]

so it's time for new batteries in my 87 hj60, after searching and reading I am going with sears/die hard 27m marine RV deep cycle (on sale right now for $89)
the only issue is that they only have 575CCA.

Is this enough? if not how much is enough? (I live in Buffalo so it gets pretty cold in the winter)

it's 24v if that matters

X2k1A

 

[amaurer]

so it's time for new batteries in my 87 hj60, after searching and reading I am going with sears/die hard 27m marine RV deep cycle (on sale right now for $89)
the only issue is that they only have 575CCA.

Is this enough? if not how much is enough? (I live in Buffalo so it gets pretty cold in the winter)

I had a 550 and it turned over pretty slow. Got a 900 now, much better!

 

[canucksafari]

I'd go for the higher CC amps. You'll notice the difference in the cold weather.

 

[dudedude]

Because there are two batteries do you get twice the cca's?
Would there be a total of 1150cca or do you only get the amps of the highside battery?

 

[canucksafari]

I don't think it works that way. The Cold Canking amps is the maximum amperage in cold weather that the battery will put out. Now they are in series, but I think that this only affect voltage - not amperage. The CC amps is only part of the equation. The other part is how long the battery will push out that amperage.

A general rule of thumb is the bigge the battery the higher the CCA and the cranking time. I've always bought the biggest battery I could fit with the highest CCA and crank time. So far it seems to have worked great.

 

[dudedude]

i just found this in an older thread


"Higher cca means thinner lead plates which results in quicker failure.
You can not buy a 24 volt battery, hence the two 12 volt batteries. This will give you more then enough cranking amps.
I would suggest to buy the biggest batteries (27 series) with the lowest cca."

https://forum.ih8mud.com/diesel-tech-24-volts-systems/246086-newb-900-cca-costco-battery.html

I am even more confused now...

 

[canucksafari]

i just found this in an older thread


"Higher cca means thinner lead plates which results in quicker failure.
You can not buy a 24 volt battery, hence the two 12 volt batteries. This will give you more then enough cranking amps.
I would suggest to buy the biggest batteries (27 series) with the lowest cca."

https://forum.ih8mud.com/diesel-tech-24-volts-systems/246086-newb-900-cca-costco-battery.html

I am even more confused now...

I am not sure that thinner lead plates means higher CCAs. Also, there is no problem buying a 24V battery. They are used all over the world and North America in numerous applications from golf carts, to fork lifts to aircraft. Just that you won't find them at Walmart or Canadian Tire.

 

[roscoFJ73]

This is from Wiki and is how I understand it.
Car battery - Wikipedia, the free encyclopedia

The deep cycle (or motive) type is designed to continuously provide power for long periods of time (for example in a trolling motor for a small boat, auxiliary power for a recreational vehicle, or traction power for a golf cart or other battery electric vehicle). They can also be used to store energy from a photo voltaic array or a small wind turbine. They usually have thicker plates in order to have a greater capacity and survive a higher number of charge/discharge cycles. The energy to weight ratio, or specific energy, is in the range of 30 Wh/kg (108 kJ/kg).

Batteries intended for SLI (start lighting ignition) systems are intended to deliver a heavy current for a short time, and to have a relatively low degree of discharge on each use. They have many thin plates,thin separators between the plates, and may have a higher specific gravity electrolyte to reduce internal resistance. Deep-cycle batteries have fewer, thicker plates and are intended to have a greater depth of discharge on each cycle, but will not provide as high a current on heavy loads. [3]

The marine deep cycle batteries are usually hybrids of the two types. On boats you they re used for cranking and when the engine is not running powering small items like navigation lights.
IMO you are better off with a cranking battery for starting and running and a deepcycle for running fridges,12v lighting for camping etc.

 

[dudedude]

So does anyone know the CCA's of two batteries in series? is it a combo of the two like the voltage or just the CCA of the highside battery?

 

[amaurer]

So does anyone know the CCA's of two batteries in series? is it a combo of the two like the voltage or just the CCA of the highside battery?

It would be the CCA of the smallest battery in the pair.

When you connect batteries the law of energy conservation says only one parameter (voltage or CCA) can double.

Series - Double voltage, same CCA
Parallel - Same voltage, double CCA

The reason being, you can't suck more wattage out of a battery than it is physically constructed to deliver, and that is completely independent of external connections (to other batteries, accessories, etc).

Independent of connections, Max wattage = Volts * CCA:

The wattage of each battery = Voltage * CCA.
The wattage of the group of batteries = Battery Wattage (each) * quantity.

Wattage of group = Batt voltage (each) * CCA (each) * quantity.

If you're clever, you can look at that equation and see that you write it like this:

Wattage of group = Batt voltage (each) * quantity * CCA (each).
OR
Wattage of group = Batt voltage (each) * quantity * CCA (each).

In each case, the Blue text is the group voltage, and Red text is the group CCA. This is just algebra, but physically those two equivalent expressions represent series and parallel arrangement.

The reason why parallel arrangements equal the lowest CCA in the group is more subtle, but its simple because if you exceed it, then the voltage starts to drop as that battery isn't doing its fair share.

 

[Greg_B]

Battery talk can can lead to much confusion.

Try this for the CCA question on two 12V in series: http://www.jd2cylservice.com/Misc11BatteryIssues.pdf

Try this for more then you want to know: Car and Deep Cycle Battery FAQ, Battery Manufacturers and Brand Names List, and

Another link so useful battery information: http://www.windsun.com/Batteries/Battery_FAQ.htm

Starting batteries have thinner plates then deep cycle batteries. High CCA batteries have even thinner plates. Thinner plates do not put up with vibrations as well as thicker plates (off-road, diesel, etc). Will it be an issue for you. Probably not. I would suggest finding the manufactured recommended CCA's for your application in your climate, and either stay with that, or go slightly higher. 900CCA is probably plenty. Any more is a waste of money (if there is a high price difference).

Yes, you can get 24V batteries. Your (our) trucks have trays for 12V batteries.

I've been trying some dual purpose batteries in my BJ74, but have not been wheeling it much (using winch, etc) to give much feedback. Put some standard Interstate Workaholics in Petra's HJ61 a few years back and have been very happy with them.

There is some good info on the second link provided about running a deep cycle bank off a standard charging system. I'll have to spend some time there when I get to that point.

hth's

gb

 

[blis]

I wouldnt worry about cca's in dual battery systems like hj, just throw two optima red tops and you will be good to go. Or just any semi-decent batteries...

 

[amaurer]

People will disagree with me, but I really like Walmart batteries. I paid $70 for a 950CCA battery and have used it for 2 years. Even if it dies every year, $70 to replace it is competitive with more expensive batteries that last longer.

 

[RufusTheDufus]

I had a 550 and it turned over pretty slow. Got a 900 now, much better!

That's on a 12v 3B though, no?

 

[Greg_B]

I wouldnt worry about cca's in dual battery systems like hj, just throw two optima red tops and you will be good to go. Or just any semi-decent batteries...

There's a whole bunch of people I know who have not had success with AGM spiral cell such as optimas, in a series configuration. AGM Spiral cell like to have the charge just perfect and the same on each, or they show problems early. As a single, or dual in parallel are ok...but two in series ala a 24V system shows this weakness.

Spend some time at the Deka site in the automotive, marine and rec vehicle sections reading the tech bulletins. While marketing is there, they also have some great battery information.

Here is one: http://www.eastpenn-deka.com/assets/base/1081.pdf

 

[canucksafari]

So Greg would you recommend the marine cranking battery as a happy medium and using a solar converter or a reducer for your 12V needs? Or is it best to stick with 2 regular cranking batteries and another deep cell for accessories and to have that charged via something like a solar converter?

 

[Greg_B]

So Greg would you recommend the marine cranking battery as a happy medium and using a solar converter or a reducer for your 12V needs? Or is it best to stick with 2 regular cranking batteries and another deep cell for accessories and to have that charged via something like a solar converter?

Figure out your needs, and use of the starting battery bank. If you’ve got a 24V truck then figure out what your 12V accessory needs will be. Decide if a converter or a 3rd deep cycle battery will be better suited to supply your 12V needs. If you decide a 3rd battery, then decide if a 2nd alternator or charging it through an isolator, then converter plus a battery minder is better for you.

Educate yourself to battery types: advantages, disadvantages.

When you’ve figured all that out, get whatever battery(ies) you feel comfortable getting.

As part of the picture, consider that your alternator (if 24V) is either 30 or 35 amp @ 24V. This is equivalent to 60-70 amp @ 12V. Consider the load on your system in the worst case you might see (night time, winter, snowing = headlights-highbeam, heater-high, wipers, etc). Figure out what this takes from your system. Give yourself a buffer. What’s left over is the excess available to power your 12V needs. Chances are there is not going to be a ton. Enough for a standard stereo, cell phone charger, etc. If you are simply using a large amp converter which can supply more, and you draw it, you are going to stress the alternator.

If you are going to have transient heavy 12V loads, want to run a 3rd battery to isolate any 12V load from the starting bank, etc…then you have moved into the 2nd alternator or converter/load manager combo. This opens up solar power as a charging option when base camped too.

I’ve heard of people going simply from a small amp converter to a 3rd battery and they seem to have not had overcharge issues, but I personally would prefer having a battery minder of some sort in the system.

Running a 2nd or 3rd battery in a 12V truck has been discussed lots, and there are various options out there I will not get into here. There is some interesting information in the 2nd link I posted which talked about pitfalls and issues to be aware of when charging an isolated deep cycle off an automotive charging system. I’ll be brushing up on that when I get to that point with the 80.

 

[Stone]

x3 on you don't need to go with the highest CCA battery in Group 27. If you compare two group 27 batteries, one with 650 CCA, and the other with 900+ CCA, in order to get a much higher CCA in the same sized case, they use thinner plates. Two 650 CCA batteries in series for your 24V 2H will be more than you'll ever need, especially if you keep them in good condition.

Like Greg B, I'm not a huge believer in expensive spiral cell batteries unless you really need the non-leak feature for funky installations or maybe you're a hardcore wheeler and you figure you might flip your rig frequently. If you really like to spend money on batteries, maybe a good AGM equivalent might do well...otherwise lead-acid is cheap proven technology.

I've converted my 12H-T into 12V, and I can crank it without any issues whatsoever...it cranks as easy as any 24V system I've ever heard...and I did own a BJ74 for a few years as a DD. In fact, I had to re-re my turbo four times due to the incompetence of ADP, and each time I installed it I had to shut off the fuel and crank it for a while to build up oil pressure before starting it up...and never once did I kill my supposedly inferior 12V battery system.

My 2 cents.

 

[toomanymachines]

I was told by an exide rep a long time ago that you should buy the largest case you can get. the plates are the thickest , but the acid stays the coolest. He stated that heat destroyed alot of batteries. If you have alot of amperage in a small case it will heat up alot faster.
I have had trouble with two smaller batteries in my bj60. I repaced it with one redtop and it started much faster(spun faster). I now have two, but it is still only a 12v system. I have never tried them in my bj70 (24V), So I cannot tell you if they would hold up to that.