What have i done to my batteries?

[cutandpolished61]

Hi All, i'm not just new to boating but also new to the 12 volt world I had to learn a lot since last summer. Not enough as it looks like, I messed up my new batteries.

I always charged my batteries when they reached 12.2 volt using a 40 amp battery charger powered by a generator. I stopped charging when the charge reached 14.1 volt. That was the reading on my sterling power management monitor. Now I bought a USB charger which also shows the voltage and to my surprise the voltage showed 0.3 volt less. I checked the voltage on the terminals and the reading on the USB charger was confirmed. With other words I undercharged my batteries from new, now wonder they have lost capacity. I should have recalibrated the sterling power management, big mistake for not doing so. Is there any way to restore the sealed lead acid batteries back to acceptable capacity?

[Alan de Enfield]

25 minutes ago, cutandpolished61 said:

 Is there any way to restore the sealed lead acid batteries back to acceptable capacity?

 

Once your batteries start to charge at 14.1 volts, they are getting near to fully charged bit they are not fully charged. They may well need a further 3 or 4 hours at 14.4-14.6 volts.

The batteries are fully charged when they have been charging at 1% of battery capacity (so if you a 400Ah battery bank, charging at 4 amps or below) at 14.4+ volts for an hour.

 

 

You may be able to recover some capacity by using an equalisation charge.

This means charging at 15.5-16 volts for about an hour. This will make you batteries seriously 'fizz' and should not be used on 'sealed batteries'.

 

This is why you should not use sealed FLA batteries - however, you have what you have so all you can do is

1) Replace them

2) Live with the reduced capacity

3) Try an equalisation charge and hope they don't boil and 'explode'.

 

You need to find a charger that can provide the high voltage - low current that you need.

Fully charge (as much as you can) with your existing charger

Then put on the 16v charger for an hour.

 

This should be done infrequently (probably every 2 or 3 months)

[MtB]

40 minutes ago, cutandpolished61 said:

I stopped charging when the charge reached 14.1 volt.

 

This is the root of your problem, especially given the incorrect calibration of the battery charger means you were stopping charging when the charge voltage was at 13.8V.

 

Received wisdom on this board is that you should set your charger to charge at 14.4V to 14.8V then monitor the charge current. When the 14.4V is reached you must CONTINUE CHARGING until the charge current falls to a value which is 1% of the battery badge capacity. (I know the units/dimensions don't match but ignore that. 400AH capacity, charge until the current has fallen to 4A.)

 

Having said all that, it take about 8 hours to do this so few people actually do it. Those who do, make a bloody nuisance of themselves out on the cut running their engines or gennies for hours on end and ruining a nice sunny peaceful day for everyone else, so maybe just buy new batteries every year or two.

 

 

 

 

[cutandpolished61]

Thanks Alan, I'll try my luck. Problems is the 14.1 volt charge was always the wrong reading on the sterling when in fact I stopped charging at 13.8 v.

 

[cutandpolished61]

3 minutes ago, Mike the Boilerman said:

 

This is the root of your problem, especially given the incorrect calibration of the battery charger means you were stopping charging when the charge voltage was at 13.8V.

 

Received wisdom on this board is that you should set your charger to charge at 14.4V to 14.8V then monitor the charge current. When the 14.4V is reached you must CONTINUE CHARGING until the charge current falls to a value which is 1% of the battery badge capacity. (I know the units/dimensions don't match but ignore that. 400AH capacity, charge until the current has fallen to 4A.)

 

Having said all that, it take about 8 hours to do this so few people actually do it. Those who do, make a bloody nuisance of themselves out on the cut running their engines or gennies for hours on end and ruining a nice sunny peaceful day for everyone else, so maybe just buy new batteries every year or two.

 

 

 

 

You are correct, we are a nuisance, hence my decision to get solar on board. But that will open another can of worms.

[dmr]

Its very difficult to get batteries fully charged and so very easy to undercharge them. On each charge you maybe get to 99%, and then on the next charge get to 99% of 99% so it gets worse and worse.

 

Sealed lead acids are not ideal for many boaters because you don't really have the option of reviving them with a big equalisation charge. Some sealed batteries are only notionally sealed so if they have some sort of cap you might be able to get them open.

 

For liveaboards two common options are expensive batteries like Trojans with some topping up and equalisation, or cheapo sealed or non sealed and replace every year or two. It feels like spring is almost here so maybe muddle through the summer and get a new set ready for next winter?

 

..............Dave

 

 

[cutandpolished61]

Just now, cutandpolished61 said:

You are correct, we are a nuisance, hence my decision to get solar on board. But that will open another can of worms.

problem is this bloody sterling monitor doesn't show me the amperage going into the 12 volt batteries, it shows it only for the 24 volt bank.

1 minute ago, dmr said:

Its very difficult to get batteries fully charged and so very easy to undercharge them. On each charge you maybe get to 99%, and then on the next charge get to 99% of 99% so it gets worse and worse.

 

Sealed lead acids are not ideal for many boaters because you don't really have the option of reviving them with a big equalisation charge. Some sealed batteries are only notionally sealed so if they have some sort of cap you might be able to get them open.

 

For liveaboards two common options are expensive batteries like Trojans with some topping up and equalisation, or cheapo sealed or non sealed and replace every year or two. It feels like spring is almost here so maybe muddle through the summer and get a new set ready for next winter?

 

..............Dave

 

 

Thanks Dave. I will certainly not spend £250 every year or two for new sealed batteries. First year is for learning the hard way. Certainly no excuse to mess it up from year two. Solar is the only option for me.

[MtB]

1 minute ago, cutandpolished61 said:

problem is this bloody sterling monitor doesn't show me the amperage going into the 12 volt batteries, it shows it only for the 24 volt bank.

 

Point of Order, the correct term is "current" please!

 

Trivial, but "amperage" is an American term and grates horribly once you realise, don't you think?

 

You need a Victron BMV-702 ammeter really, to accurately measure the charging current.

 

 

 

 

[dmr]

3 minutes ago, Mike the Boilerman said:

 

Point of Order, the correct term is "current" please!

 

Trivial, but "amperage" is an American term and grates horribly once you realise, don't you think?

 

You need a Victron BMV-702 ammeter really, to accurately measure the charging current.

 

 

 

 

Can we still say voltage? or would you prefer potential difference ? 

 

My old man was an electrician and always used the term amperage

 

...............Dave

[MtB]

7 minutes ago, dmr said:

Can we still say voltage? or would you prefer potential difference ? 

 

My old man was an electrician and always used the term amperage

 

...............Dave

 

"Volterage" would be the equivalent, Shirley?

[ditchcrawler]

30 minutes ago, cutandpolished61 said:

Thanks Alan, I'll try my luck. Problems is the 14.1 volt charge was always the wrong reading on the sterling when in fact I stopped charging at 13.8 v.

 

Do not base your stopping point on voltage it is not an indication of how full the batteries are.

 

14 minutes ago, dmr said:

Can we still say voltage? or would you prefer potential difference ? 

 

 

 

...............Dave

I just read a posting where it was referred to as Tension

[Alan de Enfield]

8 minutes ago, ditchcrawler said:

Do not base your stopping point on voltage it is not an indication of how full the batteries are.

Correct it is a combination of Voltage and Current as per :

 

55 minutes ago, Alan de Enfield said:

The batteries are fully charged when they have been charging at 1% of battery capacity (so if you a 400Ah battery bank, charging at 4 amps or below) at 14.4+ volts for an hour.

 

[Rickent]

You need a smartgauge,  Mike has a couple spare,  you might be able to strike a deal.?

[MtB]

17 minutes ago, Rickent said:

You need a smartgauge,  Mike has a couple spare,  you might be able to strike a deal.?

 

No, I have one in each boat. 

 

I have learned that half the time, the displayed value must be ignored and cannot be trusted. 

 

It tells you which half on page 29 of the manual, if you get that far without falling asleep!

 

 

[Richard10002]

1 hour ago, cutandpolished61 said:

Thanks Alan, I'll try my luck. Problems is the 14.1 volt charge was always the wrong reading on the sterling when in fact I stopped charging at 13.8 v.

 

14.1v isn’t high enough, even if read correctly.

 

You need to be at at least 14.4V for long enough for the Amps to fall to 1% of capacity, as Mike says above.

 

You will destroy your batteries if you stop charging as soon as they reach 14.1v, or 14.4v, or any other voltage you choose. You have to carry on until the Amps fall to the appropriate level.

 

In a similar way, if you get a Smartgauge and stop charging when it reaches 100%, you will almost certainly destroy your batteries.

 

You should also charge to full every other day as, for some/many/most, once a week isn’t enough.

 

and so it goes on ....... 

 

Whatever you do, you should be prepared to by new batteries every 2 or 3 years. Any longer than that is a bonus  

[Alan de Enfield]

13 minutes ago, Richard10002 said:

You need to be at at least 14.4V for long enough for the Amps to fall to 1% of capacity, as Mike says above.

And, as was pointed out in the first reply (Post #2)

[Richard10002]

4 minutes ago, Alan de Enfield said:

And, as was pointed out in the first reply (Post #2)

Given #4, the OP didn’t seem to have taken much notice of you  (or Mike).

 

More seriously..... Its a difficult concept, so often needs repeating a few times until the penny drops.

Edited March 8, 2020 by Richard10002

[Alan de Enfield]

2 minutes ago, Richard10002 said:

Given #4, the OP didn’t seem to have taken much notice of you  

I think you are (again) misreading, he has thanked me and has suggested he will give "will try his luck" by (I assume) giving the equalisation a 'go'.

[David Mack]

1 hour ago, Mike the Boilerman said:

 

Having said all that, it take about 8 hours to do this so few people actually do it. Those who do, make a bloody nuisance of themselves out on the cut running their engines or gennies for hours on end and ruining a nice sunny peaceful day for everyone else, so maybe just buy new batteries every year or two.

Use the generator to put the bulk of the charge in, preferably during the morning, then use solar to provide the lower current for several hours to completely top up the batteries. This will work even during the winter and save a lot of generator running, petrol and neighbour disturbance.

[MtB]

1 hour ago, cutandpolished61 said:

Problems is the 14.1 volt charge was always the wrong reading on the sterling when in fact I stopped charging at 13.8 v.

 

No, that is NOT the problem.

 

The problem is twofold.

 

1) You were not charging at 14.4V (14.1V is simply not enough, even if the Sterling was reading right.)

 

2) You were stopping charging just as you got into the absorption stage, which needs to run for typically four hours. 

 

 

 

 

Edited March 8, 2020 by Mike the Boilerman
spelling

[Flyboy]

2 hours ago, dmr said:

Can we still say voltage? or would you prefer potential difference ? 

 

My old man was an electrician and always used the term amperage

 

...............Dave

No, Electro Motive Force.

[MtB]

Well current is the name for the thing we are measuring, Amperes are the unit of measurement. 

 

For voltage, potential difference is the name of the thing we are measuring, Volts are the unit of measurement. Frankly I prefer PD to voltage as it is more grammatically correct.

 

"Voltage" is the odd man out as it is in widespread use and the correct term is not widely understood or recognised. We don't describe linear dimensions as "yardage", or "footage" "millimetreage" do we? Or volumes as "litreage" or "gallonage? Or weight as "poundage"? So why describe current as Amperage? 

[system 4-50]

I don't think there is much mileage left in this thread.

[Alan de Enfield]

58 minutes ago, Mike the Boilerman said:

We don't describe linear dimensions as "yardage"

Yardage is a commonly used term in the upholstery industry (the number of yards of material required) in Golf (the caddie worked out the yardage...….) and in Football (the yardage made was …..)

I'm sure there are many other examples.

 

Collins Dictionary :

 

Yardage is a measurement of the length or distance of something, expressed in yards.

Vijay Singh says the course will not play as long as the yardage indicates.

[Richard10002]

3 hours ago, Alan de Enfield said:

I think you are (again) misreading, he has thanked me and has suggested he will give "will try his luck" by (I assume) giving the equalisation a 'go'.

Given post #4 and the repeated reference to 14.1v, I think it was hard to make any assumptions.

 

Like I said, it was worth repeating, because it is not an easy concept.

 

Mike seems to agree with me.

Edited March 8, 2020 by Richard10002