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Proper Battery Charging

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Great picture of what over charging does to a battery

Use The Correct Charger!

We cannot stress enough how important it is to properly maintain your SLA batteries and to use the correct charger on your batteries.  Improper charging can have devastating effects—batteries can melt, explode, implode and/or catch fire; chargers can catch fire or end up with fried circuitry.  Not periodically checking the health of individual batteries in a series or parallel connection can result in overcharging and destroying otherwise healthy batteries should one fail. Even with today’s smart technology things can go drastically wrong!

Nuggets of Wisdom

Complete proper maintenance. Simply knowing you have a smart charger is not enough.  You need to periodically check the batteries health by getting voltage readings and ensuring everything is connected securely. Selecting the correct charger is important and can help identify potential issues, but nothing is better than a physical.  Most auto stores and scooter stores provide this service for free.  Check out the link above to learn more on proper battery care.

Never exceed 25% of a batteries capacity (Ah not CCA). Example: If your battery is 100Ah then your charger should not be greater than 25 amps.

Don’t skimp on size. Generally, you do not want to go smaller than about 10% of your batteries capacity. Example: If your battery is 100Ah then your charger should not be less than 10 amps.

Charging vs. Maintaining. Maintaining your battery is different than charging your battery. Example: A charger rated at 2 amps may keep a fully charged 100Ah battery in a fully charged state, but should not be used on a discharged battery of this size.  A charger that is too small for the battery can leave a battery in a discharged state far too long and can burn up the charger in the process.

Charger should be designed for the application. Make sure the charger being used is appropriate for the type of battery you are charging—lead acid (AGM, Gel, Wet), lithium, NiCd, etc.—they all take different charge profiles.

Use proper voltage.  Example: 12V chargers are to be used on 12V systems.  They should not be used on 6V, 24V or any other voltage systems.   The idea that ‘something’ is better than nothing is dangerous and destructive.

24V, 36V & 48V systems and multibank chargers. When you have a series connection it is OK to use a charger of lower voltage when applied to subsets of the system in equal proportion.  Example: Six 6V batteries tied together in series for a 36V system can use a 12V 3 bank charger.  Each 12V lead will span 2 of the 6V batteries (a small 12V series connection). A 12V two bank charger can charge a 24V battery bank by placing one lead on each individual 12V battery.

Find the proper battery charger.


One thought on “Proper Battery Charging”

  • http://www.etsy.com/people/DayLee?ref=si_pr Consumer Joe

    Hello, I have an older 6 & 12 volt charger of yours. The directions on the back of the charger unit; attach charger output lead to the ungrounded battery post. Makes sense to me, except there is not distinction between the charger output lead and the other lead. One is red and one is black, I have not doubt back in the day, it would of been automatic which was which. I did not buy this charger, do not have any instructions, except what is on the outside of the charger unit. The only reference is; according with polarity identification. Nothing about which is which. There is, stamped into the metal, words which seem to be where or who made to leads. I was hoping to find some sort of reference to older models. Personally, I keep all of the boxes and instructions for all of the purchases I make. As I mentioned this was not my purchase it is on loan. The last thing I need top do is have it malfunction and me have to replace it. Yes I did ask the owner of the charger, and she said it was sitting in her garage. No box no instructions, I ask if she had ever used it and she said she had not.
    The history of batteries and battery chargers, it would be good for the kids that grow up knowing nothing of the how and why's of 12 volt charging system.
    Thanks for all of your time and effort in putting this opportunity for sharing together.

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