# Best Pratice for charging batteries



## Maine-Marine (Mar 7, 2014)

Does not matter if you are charging them with Solar, Nuclear Power plant, or hand cranked device

if your set up contains more then 1 battery it is always better to connect to both ends of the "cell"

does not matter if it is 2 batteries or 20 batteries, does not matter if it is 6, 9, 12, 24, or 48 VDC!

in the below images A treats the batteries as a single cell and charges them as a single cell. all batteries will end up with the same charge - IE they will all be charged X% (as long as the load is connected in the reverse >+ to battery that is connected to the - charge and - load to battery that is connected to + charge< or pulled from the controller)

A is better for both charging and for providing power for the load!!!

Image B will charge the battery that is connected and trickle charge the next which will trickle charge the next etc, it will also draw down the load battery and then each battery will trickle down to the one being drawn from








This is assuming of course you are using the correct charger for your system... 12 for 12, 24 for 24 - ect


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## Maine-Marine (Mar 7, 2014)

Crap I misspelled "practice"


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## KUSA (Apr 21, 2016)

Maine-Marine said:


> Does not matter if you are charging them with Solar, Nuclear Power plant, or hand cranked device
> 
> if your set up contains more then 1 battery it is always better to connect to both ends of the "cell"
> 
> ...


In both A an B, you have your batteries wired in a parallel circuit. Electrically speaking, there is no difference at all. Regardless of one or the other setup, the electrical potential at each battery is the same. They will charge and discharge the same in both A and B.

I am assuming that you have good connections and proper gauge cables. If you don't then you need to fix that.


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## Maine-Marine (Mar 7, 2014)

KUSA said:


> In both A an B, you have your batteries wired in a parallel circuit. Electricity speaking, there is no difference at all. Regardless of one or the other setup, the electrical potential at each battery is the same. They will charge and discharge the same in both A and B.
> 
> I am assuming that you have good connections and proper gauge cables. If you don't then you need to fix that.


they will not charge the same.. Electricity will always take the path of least resistance.

so in B it will run from + to - and charge the end battery
then as the end becomes more charged it will trickle over to the next....etc

more info
http://www.gearseds.com/files/twobat_onechgr2.pdf

https://www.iotaengineering.com/pplib/balancedcharging.pdf <<<this is a great paper

I did not want to get this indepth BUT


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## KUSA (Apr 21, 2016)

What I said in my original post is correct.

The problem that IOTA is trying to counter is the resistance in the tiny wiring connecting the batteries. You would not have this issue if large gauge cables are used.


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## Back Pack Hack (Sep 15, 2016)

Maine-Marine said:


> ...... Electricity will always take the path of least resistance..........


Electricity will take ALL paths. Most of the current will take the path of least resistance. But if there's more than one, it will take all of them.


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## KUSA (Apr 21, 2016)

Just for grins and giggles, find out what gauge cable you have and how long each is. You can find out the resistance on this link.

https://www.cirris.com/learning-center/calculators/133-wire-resistance-calculator-table


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## Chiefster23 (Feb 5, 2016)

Back pack hack is correct. The batteries will not all charge equally, regardless of cable size. Now if you want to argue, fine. But I have some personal experience along these lines to back up my position. Norfolk Southern RR decided to build a battery powered locomotive to test out the concept. They built the locomotive with hundreds of individual batteries wired in series parallel. The whole thing was a failure and parked in short order. It was impossible to get all the batteries to charge equally and believe me they tried everthing.


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## KUSA (Apr 21, 2016)

Chiefster23 said:


> Back pack hack is correct. The batteries will not all charge equally, regardless of cable size. Now if you want to argue, fine. But I have some personal experience along these lines to back up my position. Norfolk Southern RR decided to build a battery powered locomotive to test out the concept. They built the locomotive with hundreds of individual batteries wired in series parallel. The whole thing was a failure and parked in short order. It was impossible to get all the batteries to charge equally and believe me they tried everthing.


I never said the batteries will charge equally. With the proper cables, both A and B will charge and discharge the same.

One reason the batteries will never charge equally is the fact that each battery is different. Each battery has a slightly different internal resistance value.

The only way you can ensure that each battery is charged at the same amperage is to wire them in series. According to Mr. Kirchhoff, the current in will be the same as the current out.

Looking at industrial batteries that are 2 volts per cell, all the cells are connected in series. They charge and discharge at the same current value. However, due to differences in the cells themselves, the battery must be put on an "equalization charge" periodically.

I have a degree in electronics and have worked with battery powered industrial equipment for over 20 years. Prior to that as an avionics tech.


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## Chiefster23 (Feb 5, 2016)

KUSA said:


> I never said the batteries will charge equally. With the proper cables, both A and B will charge and discharge the same.
> 
> One reason the batteries will never charge equally is the fact that each battery is different. Each battery has a slightly different internal resistance value.
> 
> ...


Not gonna argue with you. I have personal experience with this matter and the RR basically scrapped a brand new loco because the batteries would not charge equally (and it wasn't because of minor differences between the individual batteries). And as long as we're chest thumping, I also have an engineering degree. I'm done.


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## KUSA (Apr 21, 2016)

My guess is that the locomotive battery experiment was done years ago before modern battery management technology came out. It would be easily solved now.


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## Back Pack Hack (Sep 15, 2016)

KUSA said:


> Just for grins and giggles, find out what gauge cable you have and how long each is. You can find out the resistance on this link.
> 
> https://www.cirris.com/learning-center/calculators/133-wire-resistance-calculator-table


Overly simplistic. Does not take into account conductor material (copper v. aluminum v. copper-coated aluminum), number of strands, any raceway that encloses them..... or ambient temperature.


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## Chiefster23 (Feb 5, 2016)

This whole thread (including my posts, especially my posts) is off in la-la land. We’re talking about a small scale solar panel setup that’s going to be using 2 to maybe 4 batteries. From a practical standpoint it doesn’t really matter which connection method you use. So what if one method is 2 or 3 percent better than the other? It isn’t going to make a noticeable difference to this guy powering his stereo. Guys! We are way off in the weeds here.


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## KUSA (Apr 21, 2016)

Chiefster23 said:


> This whole thread (including my posts, especially my posts) is off in la-la land. We're talking about a small scale solar panel setup that's going to be using 2 to maybe 4 batteries. From a practical standpoint it doesn't really matter which connection method you use. So what if one method is 2 or 3 percent better than the other?  It isn't going to make a noticeable difference to this guy powering his stereo. Guys! We are way off in the weeds here.


I agree but I'm stuck at home and very bored because of the Chinese virus.


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## Chiefster23 (Feb 5, 2016)

Me too! Bored silly!


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## RubberDuck (May 27, 2016)

kusa said:


> i agree but i'm stuck at home and very bored because of the chinese virus.


 cause it's from china!


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## Elvis (Jun 22, 2018)

Well I worked my lead acid batteries today. I've maintained hydro and wind charged battery banks and was checking SGs on my 43,000 watt hr solar charged bank today. As someone who has been hands on with my batteries for 12 years and sold hydroelectric systems to many customers I can assure you that even with the 4/0 cables I use on larger systems it's important to correctly wire the batteries to get even charging, especially if you're running more than one string of batteries or have more than 3 batteries in a string. In addition with a solar bank you need to make minor adjustments to your charging perimeters at least twice a year as the days get longer and shorter.

Equalizing helps but if the battery bank isn't wired correctly you will apply uneven charges to the batteries. Just use a clamp type amp meter and you can check to see how balanced your charging is.


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## Maine-Marine (Mar 7, 2014)

most people who are going to go off grid are not going to have just 2-4 batteries.. they are going to have a bunch.... I set up a friends camp.. we used 10 55AH deep cell batteries and 6 solar panels (50 watt) with 1 controller and 1 converter

not sure about all your fancy degrees or experience from 20 years ago... I have however been working with solar for powering remote gas and oil meters for the last 6+ years...


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## MountainGirl (Oct 29, 2017)

Maine-Marine said:


> most people who are going to go off grid are not going to have just 2-4 batteries.. they are going to have a bunch....


Well, that's true enough. 
Here's our bunch; over 2 ton. Someone else can replace them down the road. I'm too tired. LOL







And - I'm not joining in this thread.
Just bored, felt like posting a pic.


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