What happen if I charge my 12 Volt Batteries (10AH) beyond the fully charged sign on my charger?  ?

The 3 pieces of 12 Volt Batteries (10AH) in my electric trike don't transport me anymore where I have to go.

What if I charge them beyond the fully charged sign on my charger?  

7 Answers

  • Fred
    Lv 5
    2 months ago

    Since you don't supply information on what type of battery chemistry you have:

    Just a guess: The batteries are at end of service life cycle and damaged? ... or Both! 

    Replace them!

    Source(s): Work detailed maintenance of a fleet of lead acid construction equipment. It's a sad detail! Workers develop a habit of abuse of lead acid batteries and when they no longer can ascend trailer ramps they are replaced. Store fresh replacement batteries immediately fall under a learned habit of harsh abuse! The most recent gripe involves workers reducing 30% of store fresh battery life cycle by repeatedly over charging a bank of batteries before they ever left the shop! Some one had turned an emergency disconnect off by error or an unknown impact. Instead of asking the first thing they did was place the battery bank under a charger. It's our off season and I have no idea of how may times the batteries came under a charge cycle, when I specific gravity tested the batteries, never to leave the shop, installed by another worker, (why? I had to redo the installation) (How may added charge cycles?) they had lost a great many charge cycle lives! Massive loss of money!
  • D50
    Lv 6
    2 months ago

    If your charger is "smart" enough to have a fully charged indicator, it is probably smart enough to stop charging the battery at that time so you won't heat up the battery and damage it by leaving it on.

  • Anonymous
    2 months ago

    Filling a battery is like "filling a tea cup" or "beer mug"     The rim of the cup or mug is as full as you can go and then it takes no more.  A FACT

    . Batteries get old over time and lose their ability to hold as big of a charge...as the battery deteriorates. Maybe 5 years of life.  So you need a replacement new battery.  All batteries so far, do not have unlimited recharging. The battery gets weaker and weaker as it ages.  

    . You notice the range is not as great anymore? A change for new batteries will fix that.

     The standard analog chargers can not overcharge a battery because the battery will not let it because it is physically impossible..to STUFF IT FULL.

    it is like the saying "you can lead a horse to water, but you can't make it drink"

  • Anonymous
    2 months ago

    You seem to hold a common myth: That batteries: "hold electricity". They Do Not, only a capacitor (or inductor, for an instant) do. Even then, there is only so much quantity Of electrons that can be stored. Going above rated voltage can squeeze some more Joules in a capacitor,  but at risk  of puncturing  dielectric and  ruining it.

    Similarly with a battery--over charging beyond recommended time/current can boil electrolyte, damaging plates, exposing plates to air; both will cause it to actually lose capacity..

    Have your  batteries load tested. They may be too  old,  most battery types (see Edit)  only last So long. Or, upgrade to a 36volt/15 or 20 A/Hr battery..

     I Assume these are Lead-Acid? If Li-Ion or NiCad, you need replace them. 

    Unless wet cell Aircraft type NiCad or Ni Metal Hydride, these can be topped off  with distilled water. If  separate cells, a bad one (reads under 2 volts if lead acid  or 1 volt NiCad under load) can be replaced. One bad cell can severely reduce a battery's capacity.

    @ Anon:  Edison Nickel-Iron cells,  very Old technology; Do have an unlimited life. These  are very large for their capacity, though, are only  used in solar power as battery backups..

    Source(s): . Dad was Electrician's Mate USN 20 years; he maintained batteries shipboard as part of his duties. Also worked civil service in Navy yard electrical shops another 15 years.
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  • 2 months ago

    You end up boiling away water from the electrolyte.

  • adam
    Lv 5
    2 months ago

    newer digital chargers wont over charge like that. They automatically shut off when the proper charge is executed. Old school non digital chargers will. But all that will do is damage the batteries. More than likely its time to replace those batteries.

  • Anonymous
    2 months ago


    They will not accept more charge than they are rated for.


    Perhaps I should have been clearer for the normal knuckle-dragging mouth breathers that populate this category – you will not get the extra range you want from the batteries being overcharged.

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