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Discussion Starter · #1 ·
I have a built-in ProMariner ProNautic charger on my boat. I just ran it in equalizing mode and it does an outstanding job.

I would also like to have the opportunity to equalize/desulfate batteries at home, both when I take the boat batteries home and for various other batteries (cars, emergency communication etc). The ProNautic is a great charger but it is made for stationary use, not to schlep it around, and of course it costs at least $350.-

Is there a not-too-expensive charger with desulfate mode? I found the following online:

It claims to be fully automatic and to detect sulfated batteries and then apply corrective measures. And the price is right.

Does that work?

Any alternatives?

Thanks!
 

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Schumacher chargers are low quality and some have bounced to a high voltage and destroyed batteries. Very inconsistent. There are a few posts about this by Maine Sail.

You usually get what you pay for.
 

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The best tool for equalization & charging at home, IMHO, is a bench top power supply. You don't need one much larger than 10A and 30V unless each battery is quite large in Ah capacity over 150Ah. Bench top power supplies usually come in 15V or 30V models and 15V is too low for an EQ so you need a 30V model. If you're going to spend the money on one a 20A - 30A model would be a wise choice.

* Charge battery to be equalized to 100% SOC. Do not try to EQ a battery that is not already at 100% SOC.

*Charging to full will be at your manufacturers recommended absorption voltage, eg: 14.8V for Trojan FLA or 14.4V for Lifeline AGM. To define "full" allow the current to taper to the point where it essentially stops declining. This will usually be at sub 1% of Ah capacity for flooded or 0.5% of Ah capacity for Lifeline AGM. Most AGM's can not be equalized, except for Lifeline, and GEL batteries definitely can't be equalized.

*Remove battery caps (not Lifeline) and confirm good electrolyte levels and then put them back on. NOTE: You should not EQ with Hydrocap or Water-Miser type battery cap installed, so save your original caps.

*Adjust power supply voltage to 15.5V - 16.0V while not connected to the battery, unless the power supply has a dedicated voltage sense circuit. Make sure your voltage is temp compensated to battery makers specs and is measured at the battery terminals. In other words if your manufacturer says it is OK to EQ at 15.5V @80F you can't EQ at 15.5V at 95F and voltage must be compensated down for actual battery temp..

*Once the battery has attained the desired EQ voltage, slowly adjust current dial DOWN so the power supply can just barely maintain the desired EQ voltage of 15.5V-16.0V at the battery terminals. Dialing the current back to the minimum level required to maintain the desired EQ voltage prevents throwing 10A, 20A, 30A + into a dead short should the battery fail during the EQ. EQing older diminished batteries can be dangerous so always use the lowest current possible to attain the desired EQ target voltage. All that is necessary for a proper equaalization is enough current to maintain the desired EQ voltage. I am not a huge fan of using a "one size fit all" battery charger that has an EQ feature as the current on many of them can not be capped or adjusted down to a safe level..

*Stop at two hours, let battery rest, check specific gravity. If all cells are not yet in balance start the EQ again and re-check SG either on the half hour or hour..

* Repeat again if necessary.

*If you absolutely have to walk away during an equalization TURN OFF THE CHARGER!... Alternatively you can use a wall timer, but I prefer to shut it off as this is the only safe way to know your safe...

What does equalization do?

#1 It serves to re-balance the individual series cells by applying a controlled over charge , a 12V battery has six 2V cells in series, EQing brings the low cells up to 100% SOC. If all cells are already in balance then the EQ is not really needed for "balance" purposes. If you are routinely charging your flooded batteries at 14.7V to 14.8V I've found the need to EQ for "balance" issues diminishes by quite a bit. However if you were charging at only 14.2V to 14.4V (old school FLA charging mentality) series cell balance issues will be more prevalent.

#2 It can help to shed some of the dead and clustered lead sulfate from the surfaces of the cells thus allowing more usable cell surface area to be usable.

#3 It can help to reconvert savable lead sulfate (sulfate that is in the ER on life support) back into active material. Capacity loss, from dead non-reconverted lead sulfate can become permanent in less than 30 days. EQing once every 20-25 days +/-, for 30 minutes or so, for a 24/7 PSOC use cruiser (Partial State of Charge), is a good course of action but, not really ever going to happen though. This is why routinely using a higher absorption voltage, not 14.4V for flooded batteries, really helps fight off the effects of PSOC use.. Higher absorption voltages, held long enough, do help reduce the need for EQing..

#4 Stirs up the electrolyte and helps minimize the effects of electrolyte stratification. Not usually an issue on boats using a 14.7V to 14.8V absorption but is a bigger issue in off-grid stationary use.

Mastech 3010EX

or

Mastech 3020EX

Cheap Wal*Mart grade chargers, Schumacher etc., can be flat out dangerous for EQing.. Please be very cautious when buying any automotive or marine grade chargers that claim to EQ.
 

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+1

I agree completely with MaineSail re: equalization procedures in a home/shop environment.

In addition, I agree that the Mastech power supplies are top-notch. I've had the HY5020 model for several years. It can provide up to 50 volts DC @ 20 amps.

Very useful and adaptable for many needs. I've even used this one on two occasions to provide 36 volt power aboard big Hatteras cruisers when the batteries were bad/being changed out.

Bill
 

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Discussion Starter · #5 · (Edited)
The best tool for equalization & charging at home, IMHO, is a bench top power supply. You don't need one any larger than 10A and 30V. (they usually come in 15V or 30V and 15V is too low for an EQ so you buy the 30V)..

*Once charged to full at 14.4V - 14.6V allow the current to taper to where it stops declining. (usually sub 1A)

*Remove battery caps

*Adjust voltage to 15.5V (measured at the battery terminals)

*Adjust current dial DOWN so the power supply can just barely maintain 15.5V at the battery terminals. (this prevents throwing 10A, 20A, 30A + into a dead short should the battery fail during the EQ). All that is necessary is enough current to maintain 15.5V. This is one reason I am not a huge fan of using a "one size fit all" battery charger as the current can not be manipulated.

*Stop at two hours, let battery rest, check specific gravity.

* Repeat again if necessary.

*If you absolutely have to walk away during an equalization charge TURN IT OFF... Alternatively you can use a wall timer, but I prefer to shut it off...

Mastech 3010EX

The Schumacher chargers can be flat out dangerous and can ruin batteries. Caveat emptor...
Thank you, I was hoping you would chime in.

I will order the Mastech power supply and I just saved your instructions. It is a lot more money but I prefer to have the right tool for the job.

I will also need to order a new hydrometer. I have one that is perfectly fine but somehow the rubber cork with the little piece of hose that allows to suck up the acid went missing. Oh well.

Thanks again!
 
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