Portable battery charger. What do you carry?

It is easy to keep your charger at 10 amps for hours when on a battery? What kind of charger is that?

MEXICOWANDERER wrote:
A separate answer about equalization using the HF. Worst case, using a generator where time is money for fuel and noise is anguish for the ears.

Charge however until you have to modulate (adjust) the voltage so it does not exceed 14.8. When the GC's charge rate reduces to around 18 amperes at 14.8 volts (not the easiest thing to orchestrate)change over to the HF. Try 10 amps. If the voltage surges a lot higher than 14.8 reduce the setting to 2 amps which will probably start out around six to eight. This is where the HF 6 amp charger rather than the 10 amp may be a better choice if this exercise is done on a regular basis.

Let the voltage rise slowly and when it gets to 15.5 re-check the specific gravity with a hydrometer.

Equalization is not like giving the batteries a vitamin pill. It is ONLY done when the specific gravity varies greatly from cell to cell. Equalization SHEDS PERFECTLY GOOD ACTIVE POSITIVE PLATE MATERIAL as well as forces sulfate from coated plates back into solution. What equalization is, is choosing the LEAST OF ALL EVILS to maintain a battery in the best condition you can.

Lastly, any "expert" that tells you a VRB valve regulated battery cannot sulfate is either bending the truth or ignorant of it. They are harder to sulfate and even harder to de-sulfate correctly (without damage). You can tell a VRB is sulfated when it loses capacity at an early age and a strict recharging regimen has not been maintained.

Great explanation!

I have two Optimas in their 4th year and have not detected a loss of capacity yet.

I wrote them about what I should do if I suspected sulphation. Their reply was to charge for 12hrs at 10A. That seems too easy!

HTH;
John

KJINTF wrote:
This is one of the best explanations I have seen regarding equalization of wet cell batteries - thanks Mex

"Equalization is not like giving the batteries a vitamin pill. It is ONLY done when the specific gravity varies greatly from cell to cell. Equalization SHEDS PERFECTLY GOOD ACTIVE POSITIVE PLATE MATERIAL as well as forces sulfate from coated plates back into solution. What equalization is, is choosing the LEAST OF ALL EVILS to maintain a battery in the best condition you can."

My batteries (Costco CG's) typically last 8 to 10 years, get Equalized no more than once every two years (individually per 6Vdc battery), have their SG checked about twice a year and water added once or at most twice a year. They have never been below 60% SOC and typically stay above 75% while camping. The rig is not used in the winter time.

Not sure if my use/service is "normal" aka typical or not - wondering what others do

I do the same as you except travel south in the winter and equalize 2 times a year. My Sams Club batteries are 7 years old and will last 7 days before reaching 50% soc. I always run out of water and gray tank space before I run out of battery power.

I think that is what happened to my Exide 6s. When I got them, I charged them up and took the "baseline SG." Then on recharging every time, I equalized to get them back to that SG.

I was treating them the same way as my GC2 XHDs which do want that in their specs. I ASSumed the Exides would have the same spec, but never read their recommended charging spec-couldn't find it. In fact their proper SG is a bit lower than I was using for baseline, so I was shedding them.

Later, I drew some black stuff up with the hydrometer and thought they were toast. Turned out they were fine (but shedded more than for their age no doubt) and now I don't do that anymore. Mex has made it all understandable, even to me.

This is one of the best explanations I have seen regarding equalization of wet cell batteries - thanks Mex

"Equalization is not like giving the batteries a vitamin pill. It is ONLY done when the specific gravity varies greatly from cell to cell. Equalization SHEDS PERFECTLY GOOD ACTIVE POSITIVE PLATE MATERIAL as well as forces sulfate from coated plates back into solution. What equalization is, is choosing the LEAST OF ALL EVILS to maintain a battery in the best condition you can."

My batteries (Costco CG's) typically last 8 to 10 years, get Equalized no more than once every two years (individually per 6Vdc battery), have their SG checked about twice a year and water added once or at most twice a year. They have never been below 60% SOC and typically stay above 75% while camping. The rig is not used in the winter time.

Not sure if my use/service is "normal" aka typical or not - wondering what others do

MEXICOWANDERER wrote:
A separate answer about equalization using the HF. Worst case, using a generator where time is money for fuel and noise is anguish for the ears.

Charge however until you have to modulate (adjust) the voltage so it does not exceed 14.8. When the GC's charge rate reduces to around 18 amperes at 14.8 volts (not the easiest thing to orchestrate)change over to the HF. Try 10 amps. If the voltage surges a lot higher than 14.8 reduce the setting to 2 amps which will probably start out around six to eight. This is where the HF 6 amp charger rather than the 10 amp may be a better choice if this exercise is done on a regular basis.

Let the voltage rise slowly and when it gets to 15.5 re-check the specific gravity with a hydrometer.

Equalization is not like giving the batteries a vitamin pill. It is ONLY done when the specific gravity varies greatly from cell to cell. Equalization SHEDS PERFECTLY GOOD ACTIVE POSITIVE PLATE MATERIAL as well as forces sulfate from coated plates back into solution. What equalization is, is choosing the LEAST OF ALL EVILS to maintain a battery in the best condition you can.

Lastly, any "expert" that tells you a VRB valve regulated battery cannot sulfate is either bending the truth or ignorant of it. They are harder to sulfate and even harder to de-sulfate correctly (without damage). You can tell a VRB is sulfated when it loses capacity at an early age and a strict recharging regimen has not been maintained.

Have you ever IR the temperature of the battery once it gets to 14.8 volts. I was wondering if temp + checking voltage is a effective way of desulfating a battery. The last thing I want to happen is to have a battery explode do to too high of heat.

KJINTF wrote:
Why do you good folks carry a portable charger?
Help me out what am I missing?
Is it that you do not have an
On board hard wired converter
Or a capable solar system
or the engine alternator is not connected to the battery bank

We have a small Class C motorhome so our "preparedness" choices and methods differ somewhat from those pulling an RV behind a tow vehicle.

We have five ways along with us at all times for charging of our coach battery bank:

1) Converter from built-in generator.

2) Small charger from built-in generator.

3) Converter from portable generator.

4) Charger from portable generator.

5) Alternator from idling of the main engine.

FWIW, all also have five ways along with us at all times for heating and cooling of the coach:

1) Cooling via built-in generator and roof-top A/C.

2) Cooling via cab A/C with the main engine idling.

3) Heating via built-in propane furnace.

4) Heating via built-in generator and a portable electric heater.

5) Heating via the cab heater with the main engine idling.


I was never in the Boy Scouts, but somehow picked up their Plan A/Plan B/Plan C/Plan X tendencies ... especially when out and about in an RV with us not getting any younger so as to have diminishing chances to try again in the future if a trip is spoiled from failed equipment.

A separate answer about equalization using the HF. Worst case, using a generator where time is money for fuel and noise is anguish for the ears.

Charge however until you have to modulate (adjust) the voltage so it does not exceed 14.8. When the GC's charge rate reduces to around 18 amperes at 14.8 volts (not the easiest thing to orchestrate)change over to the HF. Try 10 amps. If the voltage surges a lot higher than 14.8 reduce the setting to 2 amps which will probably start out around six to eight. This is where the HF 6 amp charger rather than the 10 amp may be a better choice if this exercise is done on a regular basis.

Let the voltage rise slowly and when it gets to 15.5 re-check the specific gravity with a hydrometer.

Equalization is not like giving the batteries a vitamin pill. It is ONLY done when the specific gravity varies greatly from cell to cell. Equalization SHEDS PERFECTLY GOOD ACTIVE POSITIVE PLATE MATERIAL as well as forces sulfate from coated plates back into solution. What equalization is, is choosing the LEAST OF ALL EVILS to maintain a battery in the best condition you can.

Lastly, any "expert" that tells you a VRB valve regulated battery cannot sulfate is either bending the truth or ignorant of it. They are harder to sulfate and even harder to de-sulfate correctly (without damage). You can tell a VRB is sulfated when it loses capacity at an early age and a strict recharging regimen has not been maintained.

Hi Mex,

Thanks for translating the Chiglish into English on the "start" setting.

Hi westend,

With a correctly maximum discharged (50%) group 29, I have instigated FIVE cycles of a Husky 40 amp battery charger and the charge level (acid SG went from 90 to 91 percent charged). I then tried EIGHT desulfation cycles on top of that and the SG did not increase on the hydrometer. So back went the charger for another. Same result. Tried a Black & Decker, not much different. I could not get the battery to fully charge. The maximum charge rate tapers too fast. Voltage droops down from 14.8 way too fast. What a waste of money connected to a generator.

So a DPDT relay connected to a timer now allows a 40 amp charge rate for an hour, switches the almost charger offline and the Harbor Freight online for 4 hours at the 2-amp rate, which usually starts out close to 8. By playing with the timer I can get a pretty full charge.

Yeah I know some three hundred dollar "smart" converters are better, but when I get serious, I slam 300 plus amps into my big battery bank, then taper at the last with the Harbor Freight set at 10 amps on a timer.

For me, common sense and a timer is hard to beat...

IT'S TIME FOR YET ANOTHER DOSE OF....

"The Harbor Freight charger DOES NOT WORK WELL ON AUTOMATIC MODE, and I do not trust it not to fail and destroy a battery. Period. With a dot.

Set the slider switch from AUTOMATIC to START. The dial is CHINAMERICAN mis-marked. START is in really MANUAL. You now have a manual charger, and this is where this charger shines. Superglue the switch to START if you have to."