Battery suicide

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wingcommander

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Hi peeps.
Long story short ....House bank 2 Trojan 6volts 5years old. start battery Numax 8years. Charge system victron 30 amp smart charger (both banks separately)and 2 x 80 watt solar via victron solar controller to house only . Split relay to keep separate until charge voltage sensed.
Shore power always disconnected when not at boat. Normally their most weekends in winter, more frequently in summer
Has been working faultless until 3 weekends ago arrived at boat to low voltage display 9v. Checked history on victron App . Its been gradually decreasing for around ten nights down to 4.7 volts and each day back to 13 - 14 v from solar .
Immediately checking batteries. Could smell the dreaded suicidal battery odour. The start battery was the culprit, shorted cell . Out it came . Checking Trojans , bone dry , topped up put on charger for circa 10 hours,disconnected charger, left boat Not hopeful
Arrived yesterday ( two weeks later) house bank sat at 12.7 overcast . SG low on all 6 cells. Fridge load on and gps to check discharge, down to 12.4 in 30min .

So my question is would the house bank boil dry due to the relay combining the two banks together due to the solar power getting above switch voltage and therfore being parallel to a short cell start battery.

I now need too rethink my set up
 
Can I ask why you disconnect shore power - meaning your nice Victron smart charger is not doing anything ??

I note that you say you have a fridge running .... mmmmm basically relying on 2x 80W solar panels to keep your house bank alive ... to power that.

5 years on the trojans ... 8 years on the start battery ? Trojans ran dry ? That means they would have been useless to power the fridge ... start battery ? maybe that ended up powering your fridge ? But you say separate .... 8 years .. not too bad .. maybe it was time to replace ?

Personally - I do not trust solar to maintain my battery banks - I look upon solar as a support system, with my Victron doing the main job along with engine run time. If mains is available - I plug in ... whether I'm on-board or not.
 
Refueler said:
Can I ask why you disconnect shore power - meaning your nice Victron smart charger is not doing anything ??

I note that you say you have a fridge running .... mmmmm basically relying on 2x 80W solar panels to keep your house bank alive ... to power that.

5 years on the trojans ... 8 years on the start battery ? Trojans ran dry ? That means they would have been useless to power the fridge ... start battery ? maybe that ended up powering your fridge ? But you say separate .... 8 years .. not too bad .. maybe it was time to replace ?

Personally - I do not trust solar to maintain my battery banks - I look upon solar as a support system, with my Victron doing the main job along with engine run time. If mains is available - I plug in ... whether I'm on-board or not.
Click to expand...
I think he means he put the fridge and GPS on when he got there, to see if the batteries would hold up.
 
wingcommander said:
Hi peeps.
Long story short ....House bank 2 Trojan 6volts 5years old. start battery Numax 8years. Charge system victron 30 amp smart charger (both banks separately)and 2 x 80 watt solar via victron solar controller to house only . Split relay to keep separate until charge voltage sensed.
Shore power always disconnected when not at boat. Normally their most weekends in winter, more frequently in summer
Has been working faultless until 3 weekends ago arrived at boat to low voltage display 9v. Checked history on victron App . Its been gradually decreasing for around ten nights down to 4.7 volts and each day back to 13 - 14 v from solar .
Immediately checking batteries. Could smell the dreaded suicidal battery odour. The start battery was the culprit, shorted cell . Out it came . Checking Trojans , bone dry , topped up put on charger for circa 10 hours,disconnected charger, left boat Not hopeful
Arrived yesterday ( two weeks later) house bank sat at 12.7 overcast . SG low on all 6 cells. Fridge load on and gps to check discharge, down to 12.4 in 30min .

So my question is would the house bank boil dry due to the relay combining the two banks together due to the solar power getting above switch voltage and therfore being parallel to a short cell start battery.

I now need too rethink my set up
Click to expand...
Sounds like the solar has been closing the relay and the engine battery has depleted the Trojans, although that would be odd. What VSR do you have ?

When was the last time you checked/topped up the Trojans ?
 
Interesting item ... Victron history ...

I find that I cannot find the Victron on BT if mains power is not on ... and that means I cannot access history.

Reading OP's post - makes me ask - if I apply mains and get the BT detected on my phone app ... does that give me history of the batterys even when mains was not connected ?
 
Refueler said:
Interesting item ... Victron history ...

I find that I cannot find the Victron on BT if mains power is not on ... and that means I cannot access history.
Click to expand...
That's correct, if the charger isn't on Bluetooth isn't oneither.
Refueler said:
Reading OP's post - makes me ask - if I apply mains and get the BT detected on my phone app ... does that give me history of the batterys even when mains was not connected ?
Click to expand...

No. The mains charger history is just that, it's own history. The OP was reading MPPT history.
 
Sorry late reply. Yes Paul , fridge and gps to load test. Yes victron solar charger to show history, Trojans last checked late October. All good levels ok , SG correct. Can't remember make of relay, may have a picture, will search. On leaving boat on Saturday, just out of curiosity i tried an engine start with the Trojans . Instant start on a 38 year old Bukh. Though I know I still need to bin them . I really just wanted confirmation that my theory is probably correct.
 
This is what I think is the culprit. My thoughts are this combined the two banks during the day. ( voltage circa 14 on solar) the failed start battery would then pull down the house , the solar would then just go into overdrive trying to keep the house charge up . Causing boiling dry .

The above are my assumptions , I can't think of any other cause .

Any feedback much appreciated , and which route would you now take for replacement?
 

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There seem to be many examples of similar occurrences. Leaving solar panels charging long term in the absence of the owner has led to several catastrophic battery fires and explosions. We were advised to disconnect all batteries completely when leaving the boat for winter. Lead acid open cell batteries seem to be perfectly OK with being left for six months and ours even survived three years, perfectly good after reconnecting.
 
Yes , I see your point Vyv . I am now considering going lithium for the house and L/A for the start seeing as I am literally starting from scratch. I understand the need to completely disconnect any charging device when not aboard, for insurance requirements.
Looks like my Santa's list is

2 x 100 ah lithium ( to fit in T 105 box )
1 x lead acid starting battery
1 x b2b ( probably go victron to keep colour scheme )
Shunt with display
Fuses for above
Anything I forgot please advise
Go fund me page ????

Allready have
Victron smart charger
Victron mppt solar charger
3 dodgey scrap batteries for weighing in ( might generate enough for one fuse )
A very understanding wife .
Used voltage sensitive relay about to be given the heave ho
 
The default Jeanneau set up doesn't use a VSR. It's got a normal relay wired to the output wire from the alternator so when the alternator is running it charges everything. I have pondered that if the alternator output isn't up to the current demand that an empty house bank would put a hefty strain on the alternator/starter battery combination, but it seems to work. That arrangement means that adding solar would only charge starter or house without necessarily linking the two banks.

My insurance hasn't said anything about disconnecting chargers when no-one is aboard, it'd be a bit of a faff as you'd have to remember to disconnect the shore power when you went to the pub. That said I've noticed that lots of industrial solar power stations often have big fires.
 
WindyWindyWindy said:
The default Jeanneau set up doesn't use a VSR. It's got a normal relay wired to the output wire from the alternator so when the alternator is running it charges everything. I have pondered that if the alternator output isn't up to the current demand that an empty house bank would put a hefty strain on the alternator/starter battery combination, but it seems to work. That arrangement means that adding solar would only charge starter or house without necessarily linking the two banks.

My insurance hasn't said anything about disconnecting chargers when no-one is aboard, it'd be a bit of a faff as you'd have to remember to disconnect the shore power when you went to the pub. That said I've noticed that lots of industrial solar power stations often have big fires.
Click to expand...


The insurance requirements is the lithium installation. It seems most insurance companies have it in the small print .
OK for lead acid.........?until they boil dry
 
WindyWindyWindy said:
The default Jeanneau set up doesn't use a VSR. It's got a normal relay wired to the output wire from the alternator so when the alternator is running it charges everything. I have pondered that if the alternator output isn't up to the current demand that an empty house bank would put a hefty strain on the alternator/starter battery combination, but it seems to work. That arrangement means that adding solar would only charge starter or house without necessarily linking the two banks.

My insurance hasn't said anything about disconnecting chargers when no-one is aboard, it'd be a bit of a faff as you'd have to remember to disconnect the shore power when you went to the pub. That said I've noticed that lots of industrial solar power stations often have big fires.
Click to expand...
I doubt very much that there is a short term problem leaving batteries charging. I reconnect and switch on in April and switch off in October. On the few occasions when the boat has been wintered afloat it was not allowed to leave mains cables connected ( in France, Corsica and Greece)
 
vyv_cox said:
I doubt very much that there is a short term problem leaving batteries charging. I reconnect and switch on in April and switch off in October. On the few occasions when the boat has been wintered afloat it was not allowed to leave mains cables connected ( in France, Corsica and Greece)
Click to expand...

Over here - you have choice :

1. Connect and leave connected .. afloat / ashore .. no difference
or
2. Disconnect and maintain yourself by occasional visits
or
3. Some yards here offer a battery maintenance service through layup

I always choose #1 in the yards - and I also do same with the boats at home.
The only limitation in the yards is not have standard heaters or dehumids running in nthe boats using more than reasonable electricy ... its unusual to see meters for each boat .. but they will check the overall consumption and if noted higher than usual - will check out to see why. Of course if you use tools etc - that would normally be seen by them and accepted.
 
wingcommander said:
The insurance requirements is the lithium installation. It seems most insurance companies have it in the small print .
OK for lead acid.........?until they boil dry
Click to expand...
Ah yes, there seems to be special requirements for lithium with the commercial regs as well, or at least they were asking about what installations people had.
 
WindyWindyWindy said:
Ah yes, there seems to be special requirements for lithium with the commercial regs as well, or at least they were asking about what installations people had.
Click to expand...

So far .. it seems the Company in Germany (via Estonian Broker) that covers my 38 has no mention of Lithium in policies ...

I'm reluctant to ask them - just in case it triggers their adding clauses !!
 
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