Battery Types and Charging Chargers

[LazyDog]

I have a car toy that seldom gets used and during winter I usually have problems starting the car. I put a normal 2amp charger and said that it was full. The car wanted to start but not good enough until a put a regular 10 amp charger did I mange to start the car.

I also noted that this battery is 6 years old and AGM battery, I wonder if I am the one killing the battery by not using the AGM type of chargers. Are the chargers actually needed

IF so I may just buy a regular acid battery since all the other cars are like these!!!

 

[Quattro Pete]

Get a charger/maintainer with an AGM mode, and hook it up to the battery every few weeks, if the car is seldom driven and not driven long enough.

My old BMW is like that. It sits outside, and is usually just short tripped here and there, once a week or so. Not good for the battery, especially during winter.

 

[nwjones18]

I'd say you need to do a load test on the battery. The voltage can show high enough to give an indication of being fully charged, but the battery is actually bad. That said I've read where AGM's do charge to a higher voltage than normal lead acid battery. Was discussed some on this thread:

AGM Size 34 Battery Maintainer

With the now almost a year old pandemic still afflicting the country, we are driving less than ten miles every ten or so days to pickup groceries at Walmart and an occasional doctor appointment. This has slowly discharge the AGM battery, and I noticed the engine cranked a little slower before...

bobistheoilguy.com

 

[Kawiguy454]

get a smart charger/maintainer like a CTek or Schumacher and leave it attached to supply the milliamps car electronics use even when shutoff. Other choice is to disconnect the battery cable.

Your old battery is toast only holding a surface charge. Nothing wrong with AGM ...its a battery

 

[LazyDog]

get a smart charger/maintainer like a CTek or Schumacher and leave it attached to supply the milliamps car electronics use even when shutoff. Other choice is to disconnect the battery cable.

Your old battery is toast only holding a surface charge. Nothing wrong with AGM ...its a battery

So what happens when a regular charger is used on a AGM Battery????

 

[Quattro Pete]

So what happens when a regular charger is used on a AGM Battery????

It under charges it / does not fully charge it.

 

[Donald]

Get a charger with an AGM mode. BatteryMinder would be my choice. But not inexpensive.

 

[y_p_w]

It depends on the type of charger. Some are 6/12V automatic sensing without any manual means to choose that. My kid left the map light on and it was reading about 3V the next day. I tried using a 3/12A automated charger (with selectable wet/AGM mode) and I think it was getting up to about 7 V when it said it was fully charged. I tried a combination of a 12V 1A manual charger and an older 1.5A maintainer (with a 6/12V switch) to get it charged up to about 9 V. Once it was there, the big charger was able to take it up to the point where I could start.