6volt battery charging

ezloader

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Hi all
Car sat for awhile battery was 4.0 volts.
Put on charger for an hour now it’s 2.0 volts.
What has happened??😳
Daryl
 
each cell is 2 volts— did you check the water/acid level— if it is below the plates just fill to plates are covered
 
A lead-acid battery that sits for a while uncharged or partly charged will convert the amorphous form of the the lead sulfate to a crystalline form. The amorphous form is usable by the battery but the crystalline form is not.

Battery maintainers are available that have a feature called a Desulfator. This supplies a high frequency pulse that converts the crystalline lead sulfate back to the amorphous form. You could try that but the battery may be too far gone to recover.

Another thing that happens to lead-acid batteries that sit partially discharged for a while is the lead plates can swell and short of the battery. There is no recovery. The battery is toast.
 
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The biggest problem I have is "freezing" of the battery in the off season in my unheated garage. Fully charged they don't freeze. But read "fully" by degrees of risk.

Once frozen they're toast.

I'm also finding that modern battery chargers include automated "failsafes" such as if the battery voltage is too low, the charger will shut down and prevent charging. I suspect this is more to protect the charger than the battery. I.e. you can build and sell a "skimpier" charger if you add layers of automation.

My charger of choice right now is a Sears "Craftsman" charger from the first year of my Model A Ownership (about 1978) which is a 6 amp charger, includes an amp-meter, and a switch for 12 or 6 volts. In other words a "basic" charger. It has a thermal "trip" if amperage goes much above 7 amps - and a reset. I have had it charge at high rate, then trip, then reset, then trip again - and go along like that even overnight. But that is not the desired condition - trip function CAN fail.

I have one battery (of about four) right now which is become a brick after perhaps a couple of winters. It reads as "open circuit" to a Volt-Ohm-Meter. It's being retained as "trade in" on a replacement.

Also, my experience with AGM (sealed) lead-acid batteries is they're not as "tolerant" of off design condition. As in they don't like being pulled flat, they freeze easier, and they are more of a "black box" than the traditional lead acid cell battery - which can be diagnosed with a hydrometer and a voltmeter.

Joe K
 
Take your battery to an auto parts store and have them do a load test on the battery. Your post indicates a possible bad cell.
 
Being in Michigan with cold storage, I have similar battery life issues. Who makes the best 6 volt battery. Seems like the Auto Zone and other chains are using poorly made China batteries.
Jon
 
when I was using the “original “ reproduction batteries they only lasted a short time,to extend the life from 2 to3 years to 4 to 5 years I put the fully charged battery in the freezer for the winter to slow the chemical reaction—- then I got a Optima and use the neglect method and got 16 years ( no maintainer,no looking at it just charging by driving with a higher than normal charge rate)
 
The "optima" and other AGM derivative batteries I've always thought best applicable to a charging/delivery system like a modern car.

I.e. charging by virtue of a "voltage regulator", no "cut-out" and possibly a 12V system. I.e. mimic as much as you can a "modern" car.

Meanwhile a 6V "Model A" lead acid battery best kept alongside the original generator (did you know that the original generator can provide up to 32 volts output? - tied to a battery that never happens.) And a "cut-out" - and "cycling". And maintaining your electrolyte level (always with distilled water.)

And playing games to "balance the loading" by driving with your lights during the day.

My consideration is that it is "all part of the charm" of a Model A - which is more like a WWII diesel sub in battery management.

I guess I can't fault anyone for "modernizing." It's all a matter of how and where you take your pleasure. I almost took a dive into hydraulic brakes - for a while.

Joe K
 
I connect my Battery Tender as soon as the car is parked. It is never in a partial discharge state. And I have mentioned before, I use Thermoil in my battery to prevent loss of acid. It also prevents corrosion around the battery. My Lead-Acid battery is well over 14 years old now.
 
If a battery will take a charge, the sulfation can be knocked off with a fast discharge like connecting it to a starter motor. Hit it hard between charges and it might make a come back. If the sulfation is too heavy then it will eventually short the cells. If one cell is damaged then the battery loses it's capacity. Some claim that certain chemical flushes will clean the plates but that can also be detrimental to the soft spongy lead in the applicable plate parts. It likely wouldn't last long if it worked at all. The way plates absorb electrolyte and then release it is severely compromised.
 
Well....If you want the best battery you'll have to change to a 12v system and put in a
Antigravity Battery. They are Lithium and they last forever. NOT CHEAP though.
Built in Jump start if the battery goes dead. And they weigh 70 percent less than a lead acid battery.
Their making noises about a 6volt battery and it would probably be the last battery you'll ever buy.
 
I have a LiPo battery in my car. On a tour a week ago the temperature was near freezing. The battery barely turned over the engine. LiPo batteries do not like cold weather. I think the current going through the battery may have warmed it up enough to start the engine. The rest of the day was fine.

The battery has a heating feature but I am not sure if it is for starting or charging. My battery was 100% charged before the cold weather. My car lives in the garage which stays fairly warm even in freezing weather. I don't drive it when it is super cold.

One big advantage of the LiPo battery is that it does not discharge very much while sitting. The battery is not ruined if it does sit partially discharged, like a lead-acid battery.
 
I have a LiPo battery in my car. On a tour a week ago the temperature was near freezing. The battery barely turned over the engine. LiPo batteries do not like cold weather. I think the current going through the battery may have warmed it up enough to start the engine. The rest of the day was fine.

The battery has a heating feature but I am not sure if it is for starting or charging. My battery was 100% charged before the cold weather. My car lives in the garage which stays fairly warm even in freezing weather. I don't drive it when it is super cold.

One big advantage of the LiPo battery is that it does not discharge very much while sitting. The battery is not ruined if it does sit partially discharged, like a lead-acid battery.

The temp sensing feature in your LiPo battery is almost certainly for charging. You're not supposed to charge them when the temperature of the battery is below freezing, so the battery management system has a sensor that disconnects the charging function if the temp is too low.

The most effective solution, if you end up confronting this problem a lot, would be to wire up a 12V windshield defroster. Turn it on and the current draw will start to heat up the battery. Run it for a few minutes and then start the car. As a bonus, you get less frost on the windshield.
 
As mentioned above, each lead-acid cell is 2.1 volts. Normal charge on a 6V battery is around 6.3V. If it's at 4 volts then that indicates a shorted cell, and it's toast.

I get my 6V batteries from NAPA, they stock them for tractors. I get my 12V batteries at Costco. I've found over the years with dozens of cars that if any battery lasts five years, after that it's on borrowed time. I had one (an Interstate 12V for my Tundra that I bought at Costco) fail at about 14 months. No questions, they warranteed it for me. Don't think that if you purchase a "84 month battery" that it's going to last 7 years.
 
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Definitely use a smart charger/tender if it’s going to sit. I have both Noco and Battery Tender brands, all work as advertised. Amazon had a sale on the 4 bank Noco, only thing is it doesn’t do 6V agm.
 
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