When do you replace a battery?

[crazyal]

I won a BatteryMINder from a company called VDO. I had a battery that the voltage was about half what it should be and when charged would quickly drop back down even if just sitting. It was out of my dozer so it's about twice the size of a normal battery. So I thought I would try the batteryminder and it didn't do a thing. Since it was also a charger I tossed it in the corner and figured I had an expensive float charger.

So this winter has played havoc with the older batteries I have. The 580k has two wired in parallel and the dump truck has a semi battery in it. All three of them I've charged with no luck. I have a Schumacher Speedcharger that can check your charging system as well as how much (percentage) of a charge the battery has. No matter how much of a charge I tried putting into it or the voltage I could never get past 30%. If I tried starting anything with it the battery would quickly die.

As a last ditch effort I pulled out the batteryminder and tried to charge that battery. A red light came on saying that it was in maintenance mode. Well I forgot about it for a few days and when I got sick of jump starting the dumptruck so I could plow I swapped it with the one the batteryminder had been charging/ desulfating. To my surprise it had a ton of power, easily started the truck in below 0 temps (large v-8). I decided to put the SpeedCharger on it to see what it read, 90%.

So now I have the battery from the dump truck being charged by it. It's been charging for at least two weeks and when I get a chance I'll check the electrolyte level and see how much of a charge it has (I think it's something like 1600 or 1800 cca so I don't want to replace it). So far the battery I revived with the BatteryMINder is working great. The plow truck has an electric (starter motor) style hydraulic pump for the blade. I'm not 100% sold on the batteryMINder yet but it just saved me having to replace a $100 Interstate Workaholic 950 cca battery.

 

[BobRip]

I won a BatteryMINder from a company called VDO. I had a battery that the voltage was about half what it should be and when charged would quickly drop back down even if just sitting. It was out of my dozer so it's about twice the size of a normal battery. So I thought I would try the batteryminder and it didn't do a thing. Since it was also a charger I tossed it in the corner and figured I had an expensive float charger.

So this winter has played havoc with the older batteries I have. The 580k has two wired in parallel and the dump truck has a semi battery in it. All three of them I've charged with no luck. I have a Schumacher Speedcharger that can check your charging system as well as how much (percentage) of a charge the battery has. No matter how much of a charge I tried putting into it or the voltage I could never get past 30%. If I tried starting anything with it the battery would quickly die.

As a last ditch effort I pulled out the batteryminder and tried to charge that battery. A red light came on saying that it was in maintenance mode. Well I forgot about it for a few days and when I got sick of jump starting the dumptruck so I could plow I swapped it with the one the batteryminder had been charging/ desulfating. To my surprise it had a ton of power, easily started the truck in below 0 temps (large v-8). I decided to put the SpeedCharger on it to see what it read, 90%.

So now I have the battery from the dump truck being charged by it. It's been charging for at least two weeks and when I get a chance I'll check the electrolyte level and see how much of a charge it has (I think it's something like 1600 or 1800 cca so I don't want to replace it). So far the battery I revived with the BatteryMINder is working great. The plow truck has an electric (starter motor) style hydraulic pump for the blade. I'm not 100% sold on the batteryMINder yet but it just saved me having to replace a $100 Interstate Workaholic 950 cca battery.

Please keep us updated on this.

 

[EE_Bota]

My Battery Minder failed early, and I got very little service out of it. I bought a different brand that does the same thing. My buddy has a third brand that does a similar thing.

I first read about it 1991 in an article about large UPS for data centers. Apparently the charging voltage is not enough to get the sulfation off once formed. It takes about 3V/cell to do that, but that will quickly ruin a battery. Smart designers produced chargers that have ~18V spikes with a duty cycle on the spikes that does not exceed charging voltage on average. It is like pulse width modulated DC.

When I was a kid, I saw this first hand, but I didn't know what I was seeing. I wanted 6V battery for something, and Dad assured me that there was a new one at the barn. I tested the voltage at 2mv..dead as a hammer. It wouldn't charge up at the 6v setting, so I would switch to 12v setting for around 5 seconds every so often.* It would then charge for around 15 minutes. I repeated that off and on for a few days, and it reached full charge as best I cold tell (it would start the target device.)

12V applied to 6 volt battery is pretty hot, since 9V would have been a good value for blasting the sulfates off a 6V battery.

I don't advocate doing what I did. I was a kid, but it was outdoors, and I stood well back. I knew how to use a meter, but other than that, I didn't know much about it, except I needed a battery, and I didn't have lots of money.


*That basic battery charger had a analog current gauge, and that is really handy for seeing what is going on with a battery. Sometimes I will log the amps at intervals and note the time and get an idea of the amp-hours put into the battery.
Frequently, it is easy to tell that a given battery charges up too quickly (current drops low quickly, and voltage has already recovered) which means that the battery has lost capacity. Desulfating chargers can sometimes recover some of that.

 

[ultrarunner]

My Battery Minder failed early, and I got very little service out of it. I bought a different brand that does the same thing. My buddy has a third brand that does a similar thing.

I first read about it 1991 in an article about large UPS for data centers. Apparently the charging voltage is not enough to get the sulfation off once formed. It takes about 3V/cell to do that, but that will quickly ruin a battery. Smart designers produced chargers that have ~18V spikes with a duty cycle on the spikes that does not exceed charging voltage on average. It is like pulse width modulated DC.

When I was a kid, I saw this first hand, but I didn't know what I was seeing. I wanted 6V battery for something, and Dad assured me that there was a new one at the barn. I tested the voltage at 2mv..dead as a hammer. It wouldn't charge up at the 6v setting, so I would switch to 12v setting for around 5 seconds every so often.* It would then charge for around 15 minutes. I repeated that off and on for a few days, and it reached full charge as best I cold tell (it would start the target device.)

12V applied to 6 volt battery is pretty hot, since 9V would have been a good value for blasting the sulfates off a 6V battery.

I don't advocate doing what I did. I was a kid, but it was outdoors, and I stood well back. I knew how to use a meter, but other than that, I didn't know much about it, except I needed a battery, and I didn't have lots of money.


*That basic battery charger had a analog current gauge, and that is really handy for seeing what is going on with a battery. Sometimes I will log the amps at intervals and note the time and get an idea of the amp-hours put into the battery.
Frequently, it is easy to tell that a given battery charges up too quickly (current drops low quickly, and voltage has already recovered) which means that the battery has lost capacity. Desulfating chargers can sometimes recover some of that.

Lots of us with seldom used 6 and 8 volt batteries do this...

I have an old commercial charger... small and weighs about 40lbs... Every so often would flip to 12 volt for more like 15 seconds and back to 6... it has worked many times.

If I were to leave it on 12 volt... eventually the circuit breaker in the charger would trip... did that once because the batter was dead and had been so for about 2 years... I got called away on something else and left with it on 12 volt... it did make a recovery...

 

[JDgreen227]

Lots of us with seldom used 6 and 8 volt batteries do this...

I have an old commercial charger... small and weighs about 40lbs... Every so often would flip to 12 volt for more like 15 seconds and back to 6... it has worked many times.

If I were to leave it on 12 volt... eventually the circuit breaker in the charger would trip... did that once because the batter was dead and had been so for about 2 years... I got called away on something else and left with it on 12 volt... it did make a recovery...

I have a charger with the 50 amp engine start feature...wonder of I could desulphate an older 12 volt battery with it using your method of flipping it to 50 amps for a few seconds and then back to 10 amps. Anybody ever try this ?

 

[chopped]

I wondered that too..

 

[KennedyDiesel]

Any Starter and Alternator guy worth his salt will tell you to replace the battery(s) at the first sign of weakness. This is not a ploy to sell you something it is to protect his work from being prematurely destroyed. Quite often a battery failure will be followed closely by an alternator failure and vice-versa. Essentially the alternator works double time trying to recharge the weak battery plus run accessories. "An alternator is not meant to be a battery charger, rather a battery maintainer" to paraphrase my starter/alt guy...

 

[EE_Bota]

I have a charger with the 50 amp engine start feature...wonder of I could desulphate an older 12 volt battery with it using your method of flipping it to 50 amps for a few seconds and then back to 10 amps. Anybody ever try this ?

I don't know what voltage that would wind up being. You could test to see I suppose.

 

[JDgreen227]

I don't know what voltage that would wind up being. You could test to see I suppose.

Too cold here right now (20 degrees) to do it outside and I have serious reservations about trying the idea in our basement...

 

[EE_Bota]

Too cold here right now (20 degrees) to do it outside and I have serious reservations about trying the idea in our basement...

Your reservations are very wise! :thumbsup: