Wiring In Series (pro vs con)

[TeddyDiver]

^ and ^^ concur

BR Teddy

Ps. Page change a bit ruined my ^'s. Rob's two last post on previous page..

[thomm225]

Originally Posted by ramblinrod

Ahem, the OP requested...

"Also, what are the pros and cons of this approach?"

After this was answered the thread developed into a debate of differing opinions over the finer points.

So what?

For anyone who isn't interested, they don't have to follow. For those who are, they can.

I don't see a problem.

If you do, the answer is simple, don't follow, AND FOR GOD's SAKE DON'T POST. ;-)

I guess I like to follow at times because it reminds me of when I was in my teens and 20's and going through basic electronics and electrical training. You guys are repeating those basic lessons.....that teenagers learn

You see I didn't really get into it but had to pass because if I didn't I would get my $2,500.00 bonus the military promised me

I had a boat to pay off!!!! (and a car)

[ramblinrod]

Originally Posted by thomm225

I guess I like to follow at times because it reminds me of when I was in my teens and 20's and going through basic electronics and electrical training. You guys are repeating those basic lessons.....that teenagers learn

You see I didn't really get into it but had to pass because if I didn't I would get my $2,500.00 bonus the military promised me

I had a boat to pay off!!!! (and a car)

Thank you for your service.

[s/v Jedi]

BTW those expensive gel cells better be made by Sonnenschein and their lifespan is 20 years.

[thomm225]

Originally Posted by ramblinrod

Thank you for your service.

Thank you, but my service was mostly tech schools and training to setup and troubleshooting Radar and IFF Systems at Forward Air Bases.

(we had large diesel generators that provided 3 Phase 400 HZ Power. You wouldn't soon forget how a radar sounded when the mech hooked up the 3 phase cables wrong)

The Grunts (0300) (infantry) and close air support pilots both jet and helo did most of the heavy lifting..............in that world

[s/v Jedi]

Here's another one of those exploded 12V batteries, that can not explode according to some....

[ramblinrod]

Originally Posted by s/v Jedi

Here's another one of those exploded 12V batteries, that can not explode according to some....
Attachment 148157

Please show me anywhere anyone stated a battery cannot explode?

Can't do it?

Didn't think so.

Thanks for the photo. Demonstrates just how dangerous a battery can be.

Short circuit any battery or create a spark near a vent while charging and this is what can happen.

This is why those who don't know how to handle batteries or modify vessel electrical systems properly shouldn't muck around with them.

The more energy stored and the faster the technology can release it, the more dangerous it is.

Part of the reason why 12 Vdc standard FLA batteries are so safe in comparison to others.

[pacific_voyager]

Originally Posted by ramblinrod

To anyone still following this thread.



Marine battery manufactures may make various battery models.



"Starting" batteries are designed to produce short duration high cranking amps for turning over cold engines with high compression.



"Deep Cycle" batteries are designed to handle longer and deeper discharges. The manufacturer may publish a number "(something) cycles" to indicate how many discharges to what depth a battery handled during their test conditions. This may or may not have anything to do with what one experiences in a real application.



"Dual Purpose" batteries are meant to serve both functions in one battery. These are usually best for a small vessel with only one battery.



Some may claim that battery retailers may place different labels on the same battery model. While this may be true of some "shady" operators, retailers with any integrity would never do this. Choose a well established retailer that has a good reputation for honest, reliable, customer service.



For standard FLA batteries, there are various degrees of quality and expected relative life span at various price points and in various voltages.



As with all product purchase decisions we make, weigh the pros and cons against your budget.



If you wish batteries to last as long as possible before replacement, be prepared to open your wallet up front.



If you wish to keep initial cost down, be prepared to replace your batteries more frequently.



For most, when weighing longevity against initial cost and life cycle cost, the decision is to go with less expensive (up front) batteries. These may actually be lower cost per cycle. ie, they will handle fewer deep discharges, but more discharges / $ than more expensive batteries.



Disregard the statements by others that less expensive batteries are not worthy of full-time cruisers or ocean crossers. Many a vessel has and will continue to circumnavigate the globe with inexpensive batteries.



Be aware that there are high and low quality models in every battery voltage available. When it comes to voltage, the lower the battery voltage is compared to the system voltage, the more batteries are required to be connected in series to achieve system voltage, and the greater the capacity loss if one battery fails because the entire series string needs to be disabled or modifications to the system made, so that the remaining batteries are not destroyed. For this reason, a single series string, such as 2 x 6 Vdc, 3 x 4 Vdc or 6 x 2 Vdc to achieve 12 Vdc system voltage, may not be a very good idea.



Same with battery design. Some batteries have deep reservoirs under the plates, that some claim are necessary to catch shed material to prevent shorts. Others claim, that most inexpensive marine battery designs rarely short, so this is a non-issue. Other batteries have deep reservoirs above the plates. There seems to be consensus that this is very important for a battery used in the marine environment.



Some have made up their own personal definitions about what an acceptable quality battery is, and suggest others never consider batteries below this imaginary, arbitrary line. Be aware that there is no magic performance line, where one battery model just above is "awesome" and one just below is "terrible". All there is are degrees of quality and hopefully, correlating longevity. Be aware that no matter how expensive the bank, it is possible for something to go wrong, and the entire bank to be killed and require replacement prematurely.



So after 20+ pages of pretty good info and some total nonsense...



In conclusion, there are few energy storage solutions more effective, more affordable, and more safe, than a house bank of 12 Vdc marine Deep Cycle FLA batteries in parallel.

Dead wrong. 2v cells just don't fail and every parallel string decreases the life of the bank by 30 to 40%.

[mitiempo]

Originally Posted by pacific_voyager

Dead wrong. 2v cells just don't fail and every parallel string decreases the life of the bank by 30 to 40%.

I agree 2 volt cells are the most durable.

Can you quote proof (a link) that shows the 30 to 40% decrease in life of a parallel string?

[john61ct]

Zombie thread, so much misinformation, really would have been better to let it lie.

But OK.

I'm not saying I find the claim at all credible myself, but. . .

Isn't the rule of thumb to not surpass 3-4 parallel banks based on some hard evidence?

[mitiempo]

Originally Posted by john61ct;24

84693

I'm not saying I find the claim at all credible myself, but. . .

Isn't the rule of thumb to not surpass 3-4 parallel banks based on some hard evidence?

I'm not sure of that as I have not seen any credible info.

I find it hard to believe that a series/parallel bank of 4 GC batteries suffers much from the parallel part.

[john61ct]

No, 4's OK but 8, 10, 12?

I've seen many trusted posters say you really should be going to a higher cell capacity like 2V to get fewer strings, 3-4 being the upper limit rule of thumb

[Zil]

Duracell is a East Penn label. Their name is on every battery.

[mr-canada]

Originally Posted by rwells36

In order to get around the backorder of a particular battery supplier for their 12v product I am considering the purchase of their 4v products which have no backorders and then wiring three (3) of these 4v 450Ah in series to achieve 12v. However, I desire to have a total of 900Ah at 12v (not 24v). Is this possible? If so, how?

Also, what are the pros and cons of this approach?

Pro: When everything is working properly you have a proper 12V system regardless if wired in series.

Con: If a battery screws up it can result in a lot of problems. One battery in the middle of the series can draw current as it tries to charge, yet can't, and the charging may be uneven.

This is why electric cars have battery charge controllers that detect faulty batteries and charge each battery seperatley. They let you know that battery X has a fault and it is time to replace it.

In laymans terms, one battery is best if you can find a battery that can handle your power load. If it fails, it needs to be replaced. In a multiple in-series system, if one battery fails you will need to test, test, test, until you identify which battery has failed and replace or repair it. Unlike an in-parallel system, if something fails you may find voltage drops below useable levels for many of your electronics.

I would not advise to use this workaround. Get a bunch of 12V batteries and run them in parallel instead based on your load and charging capability.

[mitiempo]

Originally Posted by mr-canada

Get a bunch of 12V batteries and run them in parallel instead based on your load and charging capability.

Very few 12 volt batteries are true deep cycle. Trojan has a few as does Rolls/Surrette.

Buy 6 of the 4 volt cells and wire them in series/parallel for 900 AH @ 12 volts.