Failure of Trojan batteries after 2 years and 9 months

[[176172]]

During the Summer the mains charger is off, unless there are a few really dull days and solar doesn't keep up. At other times the mains charger and the solar charging are both on (the solar is on 24/365).

Doesn't matter if i'm there or not, the charging regime is the same.

+1 my experience entirely
We seem to not be getting nearer to what caused the batteries, if it is the case they failed due to overcharging.

 

[dom]

Easy enough if you fit decent kit and set it up properly.

Mine have been on constant charge for four years and they are only cheap sealed SLA batteries.

During the Summer the mains charger is off, unless there are a few really dull days and solar doesn't keep up. At other times the mains charger and the solar charging are both on (the solar is on 24/365).

Doesn't matter if i'm there or not, the charging regime is the same.

And there's the rub, you're using your boat most days/week(?) and you're still unplugging and plugging components as required.

The OP meanwhile leaves his boat for extended periods hooked to both solar and shorepower and without the option for plugging/unplugging, etc. He is therefore totally reliant upon his SP and solar controllers working in harmony, rain or shine, to avoid either/both unnecessarily kicking into absorption mode.

This may only be reliably achieved by editing the respective charge programmes to lock them into a user-defined maintenance mode.

Personally, I too have some Victron MPPT solar controllers and T-105 batts. It's all good kit, but I always leave the boat on SP alone. I can't see what's to be gained by leaving the solar on other than saving a few pennies on electric at the risk of my batts.

 

[lw395]

...
Personally, I too have some Victron MPPT solar controllers and T-105 batts. It's all good kit, but I always leave the boat on SP alone. I can't see what's to be gained by leaving the solar on other than saving a few pennies on electric at the risk of my batts.

The main gain is insurance against your shorepower being unplugged or failing in your absense.

 

[dom]

The main gain is insurance against your shorepower being unplugged or failing in your absense.

True, although in this case the OP has remote monitoring. In my case I don't, but the marina sends an auto-generated email if SP is unplugged.

Which of course leaves the risk of a mains charger failure, although I visit the boat fairly regularly and with a 5-15% discharge per month and wouldn't be too worried about a month or so without charge.

I'm personally more worried about a fault-induced overcharge, a heightened risk for controllers like Victron MPPTs which are not specifically designed for long term maintenance apps.

 

[PaulRainbow]

And there's the rub, you're using your boat most days/week(?) and you're still unplugging and plugging components as required.

That's not correct. During Winter, both mains charger and solar charging are both on, no unplugging as required. In the Summer, the mains charger is turned off, although my setup allows the battery monitor to override the charger power to turn it on for a time if the battery voltages fall below a set level.

The OP meanwhile leaves his boat for extended periods hooked to both solar and shorepower and without the option for plugging/unplugging, etc. He is therefore totally reliant upon his SP and solar controllers working in harmony, rain or shine, to avoid either/both unnecessarily kicking into absorption mode.

This may only be reliably achieved by editing the respective charge programmes to lock them into a user-defined maintenance mode.

Personally, I too have some Victron MPPT solar controllers and T-105 batts. It's all good kit, but I always leave the boat on SP alone. I can't see what's to be gained by leaving the solar on other than saving a few pennies on electric at the risk of my batts.

In the UK, i know of no-one who has cooked their batteries on a decent, correctly configured, solar installation. I have several customers who leave it on all of the time. If someone was leaving a boat in conditions where over charging might be considered a risk, it would be better to turn the mains charger off and switch to a custom solar profile, takes all of two seconds. Leaving the solar on does save a few pence, but it is also less risky than leaving the mains charger on, especially if a custom profile is used for extended absences. For instance, a profile that is configured to keep the batteries on a low maintenance charge would be very unlikely to cause a major incident if a battery failed. The mains charger, on the other hand, would be likely to boil all of the batteries as it tried to get them up to absorption voltages.

 

[GHA]

although I visit the boat fairly regularly and with a 5-15% discharge per month and wouldn't be too worried about a month or so without charge. .

Must be *really* hot where you are for that amount of self discharge

Maybe much less of a worry than people think>>

https://www.pbase.com/mainecruising/self_discharge

 

[noelex]

Sorry, but that's all totally incorrect. The Victron controller will not behave as you have described, if the mains charger is on. It's smart enough to know the batteries are charged and it will not over charge the batteries as you describe.

They don't need to be interfaced. When the solar controller starts in the morning and the battery voltage is at float voltage, it's not too difficult to know what's going on. The Victron controller will not overcharge the batteries just because the mains charger has been on

No no

If someone was leaving a boat in conditions where over charging might be considered a risk, it would b better to turn the mains charger on and switch to a custom solar profile, takes all of two seconds.

Yes yes

If you want to leave the solar controller connected in situations there is mains charger connected especially with minimal discharge from the batteries (such as on the hard) you need to significantly alter the default parameters of the Victron controller to avoid overcharging the batteries. This will extend battery life.

 

[dom]

Must be *really* hot where you are for that amount of self discharge

Maybe much less of a worry than people think>>

https://www.pbase.com/mainecruising/self_discharge

Lol, not in Portsmouth sadly!

I just took those numbers from the Trojan data sheet, lower end of the spectrum sadly applies to me

https://www.trojanbattery.com/pdf/datasheets/T105_Trojan_Data_Sheets.pdf

 

[dom]

No no

Yes yes

If you want to leave the solar controller connected in situations there is mains charger connected especially with minimal discharge from the batteries (such as on the hard) you need to significantly alter the default parameters of the Victron controller to avoid overcharging the batteries. This will extend battery life.

Re your comments: yes, yes, yes, yes!

 

[geem]

That's not correct. During Winter, both mains charger and solar charging are both on, no unplugging as required. In the Summer, the mains charger is turned off, although my setup allows the battery monitor to override the charger power to turn it on for a time if the battery voltages fall below a set level.
It seems to me that you have clarified the issue. You dont have both shore power and solar charger outputs in the summer when you could expect the solar to have reasonable performance. You only have one source of charging when the sun is out. In winter the sun angles and intensity are so poor that there is simply no conflict from solar. You can leave your solar charging on all winter and it would provide little to conflict with the shore power. There may be the odd day when you get some solar output but negligible when compared to shore power.


In the UK, i know of no-one who has cooked their batteries on a decent, correctly configured, solar installation. I have several customers who leave it on all of the time. If someone was leaving a boat in conditions where over charging might be considered a risk, it would be better to turn the mains charger off and switch to a custom solar profile, takes all of two seconds. Leaving the solar on does save a few pence, but it is also less risky than leaving the mains charger on, especially if a custom profile is used for extended absences. For instance, a profile that is configured to keep the batteries on a low maintenance charge would be very unlikely to cause a major incident if a battery failed. The mains charger, on the other hand, would be likely to boil all of the batteries as it tried to get them up to absorption voltages.