New Batteries for a Battery Killer?

[Keeping Up]

1 minute ago, cuthound said:

That advice is to prevent stratification, a "problem" that affects stationary batteries (but not one I ever saw in a 41 year career working closely with batteries). It is not really an issue on a boat because the occasional rocking, normal charging and vibration from the engine will stir the electrolyte up. 

The guys at Varta were quite specific that although the rocking of a sea going boat would prevent stratification, the rocking and vibration on a typical narrow boat would never be enough to prevent it.

[davem399]

1 hour ago, Keeping Up said:

The guys at Varta were quite specific that although the rocking of a sea going boat would prevent stratification, the rocking and vibration on a typical narrow boat would never be enough to prevent it.

I bet there's no stratification on Tim and Pru's boat!

[MtB]

3 hours ago, dmr said:

I suspect the ops batteries have failed due to a total lack of equalisation over the winter, and all will be well now he has learned this stuff.

 

Not according to the OP...

 

8 hours ago, Richard10002 said:

Anyway, like MtB, I find that, despite knowing a fair amount about batteries, how they work, and how they should be charged, it is now clear that they have died a death - they seem to have a total capacity of about 150Ah as of this morning and, despite charging to 2% tail current, hours of equalising, for a couple of months, they have just got worse.

 

Edited March 5, 2017 by Mike the Boilerman

[WotEver]

3 hours ago, Mike the Boilerman said:

My conclusion is that charging frequently should be given more weight than it has been on here in the past. Daily or on alternate days.

I'm sure I read in one of Trojan's many online documents (they do have a lot, don't they?) words to the effect of "Charge regularly, at least once a week". 

But maybe I saw that somewhere else. I know I've read it within the last couple of weeks. 

[MtB]

3 hours ago, dmr said:

I suggest that if you have a big bank or a low demand then recharging once every few days is fine, but the longer you leave it the more effort is needed to shift the slight sulphation. Trojan actually suggest a little tickle (finishing charge) at about 15.5v (I think) on every charge, a sort of mini equalise,

 

Actually they suggest 16.2v finishing charge in their User Guide!

The other day Nick contradicted this citing the charge profile  graph in the user guide which states a finish charge voltage of 2.45v to 2.70v per cell, but the chart above prescribes 16.2 exactly.

[MtB]

22 minutes ago, WotEver said:

I'm sure I read in one of Trojan's many online documents (they do have a lot, don't they?) words to the effect of "Charge regularly, at least once a week". 

But maybe I saw that somewhere else. I know I've read it within the last couple of weeks. 

 

In which case I've been complying pretty closely with the Trojan advice on my Trojanoids (other than only charging to 100% according to my Smartgauge  ) yet I've still killed my Trojanoids pretty effectively in about three months. Or it might be four by now. 

So my question for the team is, why did this happen? Was it

A) Because each time I charged I charged to slightly less than 100% (100% on the SG but probably only 90% or 95% in actual fact), with a serious full charge to tail current of about 2% about once a month?

B ) because I charged to 100% on the SG only once a week?

C) Something else?

Because I'm shocked at how brutally rapid the degradation has been given I've been pretty close to the guidelines which people are now saying are pretty loose, and 'only' guidelines.

Edited March 5, 2017 by Mike the Boilerman

[WotEver]

8 minutes ago, Mike the Boilerman said:

Actually they suggest 16.2v finishing charge in their User Guide!

The other day Nick contradicted this citing the charge profile  graph in the user guide which states a finish charge voltage of 2.45v to 2.70v per cell, but the chart above prescribes 16.2 exactly.

???

2.7V per cell is 16.2V so where's the query?

[MtB]

15 minutes ago, WotEver said:

???

2.7V per cell is 16.2V so where's the query?

2.45v per cell is also the recommended finishing voltage. 14.7v. 

[WotEver]

See diagram 4 here: http://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf you can clearly see where the voltage rises from 2.45V per cell (14.7V) up to 2.7V (16.2V). 

See also the temperature compensation figures.

I have no idea where you find a charger that complies with Trojan's curves.  

1 minute ago, Mike the Boilerman said:

2.45v per cell is also the recommended finishing voltage. 14.7v. 

No it isn't. It's 14.7V absorption rising to 16.2V at the end of the charge as per their curves. 

[WotEver]

14 minutes ago, Mike the Boilerman said:

So my question for the team is, why did this happen? Was it

A) Because each time I charged I charged to slightly less than 100% (100% on the SG but probably only 90% or 95% in actual fact), with a serious full charge to tail current of about 2% about once a month?

B ) because I charged to 100% on the SG only once a week?

C) Something else?

Probably A.

However, they're not T-105s so who knows what their actual characteristics are?

[MtB]

16 minutes ago, WotEver said:

See diagram 4 here: http://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf you can clearly see where the voltage rises from 2.45V per cell (14.7V) up to 2.7V (16.2V). 

See also the temperature compensation figures.

I have no idea where you find a charger that complies with Trojan's curves.  

No it isn't. It's 14.7V absorption rising to 16.2V at the end of the charge as per their curves. 

 

That's the chart I'm looking at. The finish voltage dotted line is labelled "2.45 to 2.70v" at the top of the curve.

The voltage at the start of absorption has a dotted line labelled 2.35v to 2.45v.

 

[WotEver]

2 hours ago, cuthound said:

That advice is to prevent stratification, a "problem" that affects stationary batteries (but not one I ever saw in a 41 year career working closely with batteries). It is not really an issue on a boat because the occasional rocking, normal charging and vibration from the engine will stir the electrolyte up. 

Although stratification can (according to Trojan) also occur due to undercharging. 

1 minute ago, Mike the Boilerman said:

That's the chart I'm looking at. The finish voltage dotted line is labelled "2.45 to 2.70v" at the top of the curve.

The voltage at the start of absorption has a dotted line labelled 2.35v to 2.45v.

Yup, so you rise from14.7V to 16.2V for best charge. You can of course choose the lower voltages for a less effective charge profile. 

[MtB]

16 minutes ago, WotEver said:

Probably A.

However, they're not T-105s so who knows what their actual characteristics are?

 

I think it was B 

15 minutes ago, WotEver said:

Yup, so you rise from14.7V to 16.2V for best charge. You can of course choose the lower voltages for a less effective charge profile. 

Nick was on here the other day arguing the opposite.

[WotEver]

Just now, Mike the Boilerman said:

Nick was on here the other day arguing the opposite.

Good for him. 

[MtB]

14 minutes ago, WotEver said:

Good for him. 

Yes someone mentioned this 16.2v 'finish voltage' and he jumped on it contradicting it, citing the chart in the User Guide.

[WotEver]

1 minute ago, Mike the Boilerman said:

I think it was B

Probably a bit of both but if they were truly T-105 clones then I think they'd have responded better to desulphation. 

[MtB]

21 minutes ago, WotEver said:

Probably A.

However, they're not T-105s so who knows what their actual characteristics are?

 

I'm tending towards B ) as the cause. 'Storing' batteries at less than 100% SoC is something I've been doing almost all the time, given I discharge them for  week before recharging.

[WotEver]

Just now, Mike the Boilerman said:

Yes someone mentioned this 16.2v 'finish voltage' and he jumped on it contradicting it, citing the chart in the User Guide.

Without seeing the context I can't comment but if he was making the point that you don't have to finish at 16.2V then I agree with him (otherwise Trojan wouldn't have shown an alternative lower voltage). If he was saying that you shouldn't finish at 16.2V then I disagree with him. 

[WotEver]

1 minute ago, Mike the Boilerman said:

I'm tending towards B ) as the cause. 'Storing' batteries at less than 100% SoC is something I've been doing almost all the time, given I discharge them for  week before recharging.

If that is the case you've maybe uncovered why they're cheaper than T-105s. They don't desulphate very well. 

[Richard10002]

3 hours ago, AndrewIC said:

So on your figures, your nominal bank capacity, at new, was ~330Ah, and you are discharging them by ~200Ah, so to about 39%, twice a week, every week, so in 2 years you're getting ~700 such cycles out of a set. Am I missing something, because that sounds pretty good?

You have mixed the brief bit about my previous set of Vartas, where I didn't go into the charging regime, and the more detailed bit about my current Trojans.

The charging regime I describe relates to the Trojans, nominal capacity 450Ah, down to 50% twice a week.

Prior to getting the Smartgauge and the Trojans, I have always charged, (mostly), when the voltage has been down to 12.2v, and charged at 14.8v until tail current is less than 2% of capacity - usually 2A to 4A, so I'd guess that's what I did with the Vartas.

I'd say that, with the Vartas, I used about 300Ah a week, discharging twice to 50%, so 200 x 50% DoD cycles in 2 years. I think I became a bit more profligate with power when I got the Trojans

to dmr: I've been equalising about once a month for a few hours since I got the Trojans in May 2015 so, unless I'm doing it wrong, I've been doing it right  

my charger has an equalisation mode at 15.5V, so I can't get to 16.2v

to smileypete: I don't get to see my batteries bubbling away as they are on the counter, under the cruiser stern. I can see one, which has always bubbled away when I've looked at it.

I took the SGs for the first time in a long time a couple of weeks ago, after a charge to low tail current, and a few hours of equalising. The cells were all over the place, varying from 1.236 to 1.262. If they are sulphated, and recoverable, my life is too short to "mess about" any more.

If what I do isn't good enough, I've decided to give up trying to lengthen the life of my batteries, and accept my fate of new ones every 2 years.

I suspect Mike might be joining me

[WotEver]

15 minutes ago, Richard10002 said:

I took the SGs for the first time in a long time a couple of weeks ago, after a charge to low tail current, and a few hours of equalising. The cells were all over the place, varying from 1.236 to 1.262

This clearly demonstrates that they are in severe need of equalisation. How often have you topped them up?

[MtB]

32 minutes ago, Richard10002 said:

If what I do isn't good enough, I've decided to give up trying to lengthen the life of my batteries, and accept my fate of new ones every 2 years.

I suspect Mike might be joining me

 

Oh if only I could get two years out of a set of batteries. Two months is the best I can manage at the moment before noticable degradation sets in!

[AndrewIC]

38 minutes ago, Richard10002 said:

You have mixed the brief bit about my previous set of Vartas, where I didn't go into the charging regime, and the more detailed bit about my current Trojans.

Sorry, you're right. I also seemed to think there were 365 weeks in a year.... Been a long day!

[Richard10002]

1 hour ago, WotEver said:

This clearly demonstrates that they are in severe need of equalisation. How often have you topped them up?

I agree about the equalisation, but I've been equalising for hours each Sunday for the past few weeks, (probably 4 hours or so).

a few months ago one cell was was actually below the top of the plates, but all the others were fine, and had been over the time I'd owned them.

As I've said, if what I do isn't enough to get the many years that others get out of batteries, I am lucky enough to be able to pay the price

[ditchcrawler]

11 hours ago, Richard10002 said:

I agree about the equalisation, but I've been equalising for hours each Sunday for the past few weeks, (probably 4 hours or so).

a few months ago one cell was was actually below the top of the plates, but all the others were fine, and had been over the time I'd owned them.

As I've said, if what I do isn't enough to get the many years that others get out of batteries, I am lucky enough to be able to pay the price

I would suggest if you dont need to top them up with water you are not charging at a high enough voltage to equalise. What sort of SG reading did you get on the cell that was low in water.