Battery capacity at anchor.

[piratos]

If you change to Lithium you will most likely need to move the bowthruster to the port engine, keeping the Tsb engine just for the domestic systems.

12V is about 50%, which means if the batteries are good you have used 270Ah in the evening/through the night, which is an awful lot. Either you have something using excessive power or your batteries are no good.

Running them down to 11.7, as you say you did in the past, is extremely bad for them and may well have killed them. They need to be checked.

Hello - first of all thanks your thoughts.

I agree that the problem is that I use too much power during nicht. Thats the reason I am/was considering Lithium for consumption only, and charging consumption during passage via Battery to Battery. Thats one idea. Of course that doesnt solve the problem with the huge consumption, which I still think are the fridges.

11,7 V in the morning is not acceptable. First idea was that maybe one of the batteries was broken, and I disconnected them one by one and checked. At the moment I only have the possibility to check Volt, and they were all with 12,7V idle.

Whith dayly trips I guess that the batteries are fully laden at the evening, and they still end up with 12 Volt in the morning. For instance I crossed from Dubrovnik area to Italy yesterday and this morning as usual 12 V before generator was started. At the moment solar is charging, and the Victron charger say 13,4V and 11A. They do change to absorbtion and float later though.

 

[Bouba]

Personally speaking…I prefer the generator to have regular exercise

 

[PaulRainbow]

Hello - first of all thanks your thoughts.

I agree that the problem is that I use too much power during nicht. Thats the reason I am/was considering Lithium for consumption only, and charging consumption during passage via Battery to Battery. Thats one idea. Of course that doesnt solve the problem with the huge consumption, which I still think are the fridges.

270Ah overnight is a lot, you need to fit a battery monitor and see just where that power is going. Lithium isn't going to help on it's own, you still have the problem of replacing that 270Ah in the morning. With a big battery charger powered by the generator you could significantly reduce generator runtime though. If you do decide to fit Lithium, the Stb engine starting will need to be moved to the port batteries, you will not be able to start the engine from Lithium.

11,7 V in the morning is not acceptable. First idea was that maybe one of the batteries was broken, and I disconnected them one by one and checked. At the moment I only have the possibility to check Volt, and they were all with 12,7V idle.

Whith dayly trips I guess that the batteries are fully laden at the evening, and they still end up with 12 Volt in the morning. For instance I crossed from Dubrovnik area to Italy yesterday and this morning as usual 12 V before generator was started. At the moment solar is charging, and the Victron charger say 13,4V and 11A. They do change to absorbtion and float later though.

If the batteries are low 13.4V doesn't sound correct, that's a float voltage for lead acid. What are the settings for the solar controller ?

 

[Hurricane]

Personally speaking…I prefer the generator to have regular exercise

Ahh - so you are the noisy one in those quiet peaceful anchorages.

 

[Bouba]

Ahh - so you are the noisy one in those quiet peaceful anchorages.

I started life with a portable petrol generator…fellow boaters literally begged me to stop.
Now, I can stand on deck and pretend to be looking for the noisy boat

 

[Momac]

I started life with a portable petrol generator…fellow boaters literally begged me to stop.

My petrol generator experience has not been good. I never found it very efficient at powering the battery charger and the noise , the weight of the generator and the need for petrol were all a bit of a nuisance.

This month I bought a power bank which I propose to be charged up when on shore power . I used it on a recent short boating holiday to power the on board battery charger which has very effectively improved the on board domestic bank capacity .

 

[Bouba]

My petrol generator experience has not been good. I never found it very efficient at powering the battery charger and the noise , the weight of the generator and the need for petrol were all a bit of a nuisance.

This month I bought a power bank which I propose to be charged up when on shore power . I used it on a recent short boating holiday to power the on board battery charger which has very effectively improved the on board domestic bank capacity .





View attachment 194027

I had a power pack when I lived in the middle of nowhere in Africa…in those days it was just a lead acid battery inside…but it could start a car and power a portable fan…a real life saver.
I believe that some of the power packs available now are actually from recycled early electric cars

 

[Tranona]

My petrol generator experience has not been good. I never found it very efficient at powering the battery charger and the noise , the weight of the generator and the need for petrol were all a bit of a nuisance.

This month I bought a power bank which I propose to be charged up when on shore power . I used it on a recent short boating holiday to power the on board battery charger which has very effectively improved the on board domestic bank capacity .





View attachment 194027

That is a hugely expensive and inefficient way of adding a small amount of additional battery capacity. Charging a 12v battery with 240v then using the inbuilt inverter to get 240v output to charge a 12v battery. Sort of OK if you have bought the device for the sort of application it is designed for and this is "bonus" use, but if you want extra capacity on your boat surely cheaper and simpler to just add another battery.

 

[Momac]

That is a hugely expensive and inefficient way of adding a small amount of additional battery capacity. Charging a 12v battery with 240v then using the inbuilt inverter to get 240v output to charge a 12v battery. Sort of OK if you have bought the device for the sort of application it is designed for and this is "bonus" use, but if you want extra capacity on your boat surely cheaper and simpler to just add another battery.

A separate lithium battery , charger , solar controller and inverter probably would cost less but would require fitting.

The battery capacity of the power bank is 2073Wh which is 172Ah at 12 Volts. Lets say 95% of that is available and 90% efficiency so that's 147Ah available.
So that would need 294Ah of lead acid batteries at 50% available energy to achieve the same capacity.
I have two 260Ah of lead acid battery capacity in the domestic bank so the power bank effectively doubled the capacity on board. I don't call that 100% uplift a small amount of additional capacity.

The battery bank took no installation at all other than lifting it on board so what could be simpler?
The battery bank can be fully charged from shore power in about 2 hrs.

For sure there are cheaper alternatives. I didn't say it was cheap but nor did I mention the cost.

 

[Tranona]

For sure there are cheaper alternatives. I didn't say it was cheap but nor did I mention the cost.

I know you did not mention cost - but the difference is not trivial at £1000 - 2 or 3 times the cost of other ways of getting the same capacity.

 

[Momac]

I know you did not mention cost - but the difference is not trivial at £1000 - 2 or 3 times the cost of other ways of getting the same capacity.

I didn't say it was cheap.
I am happy with my purchase,

 

[wonkywinch]

I believe that some of the power packs available now are actually from recycled early electric cars

I honestly find that hard to believe.

 

[Bouba]

I honestly find that hard to believe.

From Chevy Bolts....