Why are Maintenance FREE batterys harder to re charge ?

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Why are Maintenance FREE batterys harder to re charge ?


Post by Motorcyclemike » Sat Jul 26, 2008 3:14 am

When i need to re charge a Maintenance Free Battery you are Not Supposed to charge them at a High Rate like 10amps...you must use about 2 amps...why is that ?

And beings i am running a 65A Generator / Cycle Electric regulator and a 18 amp hour battery......are the Maintenance free harder on the generator ?

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Post by FlatHeadSix » Sat Jul 26, 2008 3:50 am


Heat kills more motorcycle batteries than any other cause. High rates of charge in low capacity batteries will generate high amounts of heat. The heat warps the plates inside the battery and destroy it by causing internal shorts when the plates start touching each other. Other factors involve the coating on the plates but there is too much chemistry involved to try to explain that here. Just believe that less is better, if you cook the battery, its cooked!

As for the generator, they really were not designed to bring a completely discharged battery back to full charge, if you try to make them do that they will literally work themselves to death. Heat is the enemy here also, a generator which is trying to recharge a dead battery is working above its rated capacity and generating lots of internal heat as well as electricity, the commutator sectors on the armature will melt down and fuse together and destroy the generator. That's why the police units had a blower fan attached to the end of the generator.

So, the answer is to have a good battery and keep it charged by using a trickle or float charger which usually will not push more than one or two amps amps into the battery.


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Re: Why are Maintenance FREE batterys harder to re charge ?


Post by 58flh » Mon Jul 23, 2012 12:23 pm

I have a sealed AGM batt. -10amp,-320cca.---I gan chrge it in 2 min. off a car alt. & its got 12+ volts in it!--Now these batts, are not affected by heat or vibration!,They welcome it!.--Any way it was my fault the batt discharged cause I left the light on all night not knowing ofcoarse!-(7hrs). When I went for my morning ritual ride, I had the oillight barely glow!--I jumped it with a car battery & it had a 100amp alt. in it. I left the cables on for 2-4 min. & it was at 12+ volts after I disconnected all ofcoarse!. Noy had a problem since & its been months!----As far as charging (absorbed glass mat batts)--They recomend slow trickle chargers or tenders!----Richie 8) This is for a (AGM-type batt),--A maintenance free is different as they have lead-acid plates in them. Still a slow gharge is recomended.--hope this helps! 8)

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