Charging batteries

if I have six batteries charging in parallel will all batteries charge the same? That’s if all are good batteries to start with. Will all discharge the same? I should know this but this old head is not thinking right this morning,thank you.

 

Here is an article I received written permission to post on other forums, years ago.
SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

 

Thanks for the article. My batteries are wired exactly like example #1 which I am going to change.

 

Is the charger big enough to equalize 6 batteries at the same time?

 

I tried to find another article that was written some time back, regarding strings of batteries and their charging characteristics. Unfortunately, I was unable to do so.

The long and short of it is, it is always better to wire batteries in series, whenever possible. On one of my solar systems, I have 6 volt DC golf cart batteries in series, for more equalized charging.

Definitely have a look at Method 4 of the article I posted, regarding wiring your batteries for the most equal charge and discharge of batteries in parallel.

 

It appears that Method 4 results in three copper leads being attached to the same terminal, one positive and one negative, on the middle two batteries. Is this a problem, or can it be?

 

How do you go about equalizing each battery? After awhile two of my battery’s will not charge pass 80%. I’m asking all of this because I’m in the process of going solar for my out side shop. It seems as if two battery’s discharge faster than the other four.

 

@Asia-Off-Grid

Can I use these to wire 4 batteries using method #4? One battery lead (+ & -) to a post on each bus,​

then the charge controller and inverted added to the first and last on each block. Sorry for the childish drawing.

 

To come even close to equalizing those two batteries will require the required Mfg Rates of Charge and then the Finishing Rate. To accomplish the finishing rate you will need a charging source that can be varied to a scale provided by the Mfg. This will require knowing/controlling volts, amps, temp and even hydrogen output combined with corrected electrolyte specific gravity. This is just the basics.

 

This is one of the best articles I've seen on this topic in a long time.

Thanks for posting.

 

Asia-off-grid, thank you for the reference, the wife may shoot you, but I spent a couple very enlightening hours on that site. As good a discussion of batteries as I have read, both the technical and practical. As usual in tools, power sources, and in life, it is the little details that jump up and bite you in the a**. The discussion on how to connect batteries in parallel was the best I have ever read, and the actual results as far as battery charge and discharge rates, for batteries in parallel at last explains why the systems that I have seen were connected and makes more sense than that is the way it is done. Have to add that to the importance of low resistance in power distribution systems, and balancing the loads for generators. At 100 amps,current, fractions of an ohm are important.

 

I don't see how it could be a problem? Just make sure the like cables are of the same gauge and length.

Equalization should depend on your particular manufacture's specifications. My current FLA (Flooded Lead Acid) batteries, off the top of my head, are equalized at 15.5vdc, if I am not mistaken. If they are AGM, Gel, etc., this will not apply.

On my very first solar installation ever, I ran 4 - 100 AH batteries (I believe they were, anyway) in parallel, wired to two bus bars, then to a PWM controller. Sadly, I slowly murdered those batteries. I never checked SG (Specific Gravity), I didn't equalize them, ever. I only checked the electrolyte levels when it came to mind. What's worse is, I filled them with tap water, rather than distilled or de-ionized water. (I gave them each a wonderful funeral, though.) They were wired in parallel. The only thing I got right was, I had their cable gauges and lengths identical.

There was something else I wanted to say here, but, my train of thought derailed. I'm functioning from 3 hours sleep, this morning. My apologies. I will try to think of it after and post in another reply.

Firstly, you have me confused a bit, here. You are talking about wiring your batteries using method 4, but your diagram is similar to method 3.

Secondly, your batteries will not be equally charged, or drawn from, according to your diagram. The inverter is going to draw the most energy from the bottom battery, while the least from the top, when under a load.

Let me know when she is coming. I will hide.

 

Your right. 4 does look the simplest if I can make it work in my space.

 

If you can, that would be your best bet.

 

What does your setup look like?

 

I agree , ^^^^^ 4 is the best if your GO AGAINST the RULES !!

Sloth

Think of many ways home , ya always pick the easy one , so the long route road is not worked out & grows MOSS !!

Do solar once & be happy , Play & OK , but if it fails , go back to the first line in this !!

 

While lead acid batteries have a lot of short comings and are actually fairly easy to destroy, over charging, over discharging, and leaving uncharged do them in quick, they are not nearly as touchy as lithium-ion that have the ability to catch fire or blow up if overcharged or shorted. With any battery, the charger or controller and following the manufacturers rules are the only way to get good service and your money out of them. A cheap controller will not protect and maximize your solar cells out put or your battery life and a cheap square wave inverter can destroy your electronics as well as being inefficient. Solar is still an art and the best way to learn about is still to profit from others mistakes, saves time, money, and a lot of grief.

 

Believe it or not, I had a 100+ AH 12v (FLA) battery explode here, while I was away in the US, some years back. Fortunately, the "Boss" wasn't nearby when it happened, or she would have been burned from the acid. (The batteries were located under a staircase.) Until today, I have no idea what caused it to happen. I know she has been scared to be near batteries, of any size, since then.

Agreed. I just don't understand why people would pour countless dollars into a battery system, then buy a cheap, often fake Chinese crapola charge controller, to charge their batteries.

 

Here are some resources that may benefit anyone who wishes to know more about batteries:
The Battery Bible - PDF
Handbook Of Batteries, 3rd Edition - PDF
Batteries - Folder (Includes both files listed above.)