Brand new leisure batteries going flat

[Johny London]

Hi All,

I picked up my newly built boat in May. It has 4 leisure batteries (100amp hour according to the d of c though they are tricky to get at) and I fitted a Victron 3000 inverter/charger. Only ever used the engine for generating. These days, I'm running the engine for three hours a day and by the next morning the batteries are down to like 11.7 volts or less. The only thing on overnite (aside from the inverter) is the fridge which supposedly takes .52kw/h, and the microwave with its digital clock. I have two or three hours of laptop in the evening for tv etc, and an hour or two of music through a 240v amp which is turned off (not standby) when not in use. Microwave some times for 5-10 mins. The batteries didn't used to go this flat, I can't think what I might be doing differently to cause this? When I first had the boat I was cruising a lot more, though I'm not quite sure when this apparent discharge started.

The fan belt squeaks for a minute when I start the engine but reads well over 14v when charging. A while after and they sit nice and high around 13v.

Surely not knackered the batteries already???

Edited August 29, 2016 by Johny London

[Robbo]

Sounds like your not fully charging enough. Do you use any monitor to show you what's happening when charging your batteries?

[chubby]

I can t help with technical details & there are many on the forum who are extremely knowledgeable.

But , as i see it the word " microwave " is not good . Why use one ? They re only ever going to contribute to problems . Fridges are very juicy , microwaves are juicy . 240 v amplifiers ...? i don t know if they re juicy but its another drain on the batts cos the inverter needs switching on to use it .

Any 12v alternatives possible .

I suspect the your power needs are exceeding your charging routine and over time your batts are being damaged , but as i say im no techy .

Hope u get some better help , i m sure you will but i suspect you may need to rethink your onboard power requirements or rethink your charging routine

cheers

[Paul C]

I can t help with technical details & there are many on the forum who are extremely knowledgeable.

But , as i see it the word " microwave " is not good . Why use one ? They re only ever going to contribute to problems . Fridges are very juicy , microwaves are juicy . 240 v amplifiers ...? i don t know if they re juicy but its another drain on the batts cos the inverter needs switching on to use it .

Any 12v alternatives possible .

I suspect the your power needs are exceeding your charging routine and over time your batts are being damaged , but as i say im no techy .

Hope u get some better help , i m sure you will but i suspect you may need to rethink your onboard power requirements or rethink your charging routine

cheers

 

Microwave uses a lot of power but for a short time - it is not a massive issue.

 

However, the fact that there appears to be no proper battery monitoring (yes there's some voltages quoted, but they aren't meaningful) points towards a charging regime which is consistently undercharging the batteries - 3 hours isn't enough to get anywhere near 100% SoC. I am a bit disappointed a new build boat has poor access to batteries too. (And no solar power).

[Richard10002]

Have you any idea of how many AmpHours you are using each day. What type of Alternator have you got, (Max Amps?). Have you any means of charging other than the engine? Have you got a monitor like a Smartguage, (£125+/-), or a NASA BM1, (£100+/-), or both?

 

You are almost certainly not charging your batteries to 100% ever, so the capacity will gradually decline to the point where they are knackered.

 

Without any monitoring instruments, you should try running the engine for a whole day, just like you would when cruising, and see what effect that has. Do it for a few days and see how it goes

 

Buying both a Smartguage and a NASA BM1 will probably save you at least their cost in knackered batteries over a couple of years

Edited August 29, 2016 by Richard10002

[WotEver]

Without a doubt you have been chronically under charging your batteries for the last 3 months. They have subsequently sulphated and lost probably two thirds of their original capacity. A good long equalisation charge may go some way towards recovering them but they will never be anywhere near original capacity again.

 

I suggest you invest in a Smartgauge and an ammeter before you consider replacing the batteries otherwise you'll just be in the same place again in another couple of months.

 

Tony

[Alan de Enfield]

The number of times people 'roll their eyes' at me when I tell that they may need to run their engine 4 hours a day and 8 hours a day at weekends - and that is not for heavy users.

 

The replacement of electricity is probably one of the most expensive 'consumables' on a boat - just the diesel alone (say 35 litres per week) will cost £20+ (or to put it another way £80 per month). That is probably more than people spend on electricity in a small house.

Add in the additional costs of 'wear & tear' and the need to service / oil change your engine every 100/200 hours and the costs add up.

Add (say) £400 for 'consumable' batteries which you can kill within a few weeks and it all starts to mount up.

 

It makes the purchase of the right equipment (a GOOD monitoring system & solar panels) cheap by comparison.

 

I can understand when folks say that having a 'winter mooring' and paying mains-rate' (10p per unit in our marina) can be cheaper than staying bank-side.

[MtB]

Hi All,

I picked up my newly built boat in May. It has 4 leisure batteries (100amp hour according to the d of c though they are tricky to get at) and I fitted a Victron 3000 inverter/charger. Only ever used the engine for generating. These days, I'm running the engine for three hours a day and by the next morning the batteries are down to like 11.7 volts or less. The only thing on overnite (aside from the inverter) is the fridge which supposedly takes .52kw/h, and the microwave with its digital clock. I have two or three hours of laptop in the evening for tv etc, and an hour or two of music through a 240v amp which is turned off (not standby) when not in use. Microwave some times for 5-10 mins. The batteries didn't used to go this flat, I can't think what I might be doing differently to cause this? When I first had the boat I was cruising a lot more, though I'm not quite sure when this apparent discharge started.

The fan belt squeaks for a minute when I start the engine but reads well over 14v when charging. A while after and they sit nice and high around 13v.

Surely not knackered the batteries already???

 

 

As others have pointed out, three hours is nothing like enough. In round terms, with a proper charger, it seems to take 3 to 4 hours to bring a 50% SoC battery up to about 85% SoC, then a further 3 - 4 hours to get up to 100%. Charging a battery is like filling a lock. The closer to full it gets, the slower it fills.

 

And you only mention using the engine alternator. This won't be capable of charging anything like as quickly as a proper 3 stage marine battery charger. DO some homework on understanding battery charging, then buy a Smartgauge, a BMV1 ammeter and some new batts and start again!

[Robbo]

The number of times people 'roll their eyes' at me when I tell that they may need to run their engine 4 hours a day and 8 hours a day at weekends - and that is not for heavy users.

 

The replacement of electricity is probably one of the most expensive 'consumables' on a boat - just the diesel alone (say 35 litres per week) will cost £20+ (or to put it another way £80 per month). That is probably more than people spend on electricity in a small house.

Add in the additional costs of 'wear & tear' and the need to service / oil change your engine every 100/200 hours and the costs add up.

Add (say) £400 for 'consumable' batteries which you can kill within a few weeks and it all starts to mount up.

 

It makes the purchase of the right equipment (a GOOD monitoring system & solar panels) cheap by comparison.

 

I can understand when folks say that having a 'winter mooring' and paying mains-rate' (10p per unit in our marina) can be cheaper than staying bank-side.

I think 4 hours a day is way over when you start to monitor your charging tho and know how to read what the monitor is saying.

[Alan de Enfield]

I think 4 hours a day is way over when you start to monitor your charging tho and know how to read what the monitor is saying.

 

If you have good monitoring equipment and know how to use it and are prepared to amend you charging regime to suit - them I agree.

 

For those without the 'right equipment' then I think it is a good guideline.

 

An engine alternator will probably effectively put out 50% of its rated output when charging a battery (100% for the first few minutes, tailing down to 2% after a few hours.

 

Lets say I am a 100Ah per day user (Fridge @ 45 AH/day, TV, PC, Lights, pumps etc etc)

 

To replace that I really need to generate 120Ah (usage + 20%)

 

If my 75A alternator is working at 50% then I am actually averaging 37a

 

37A will therefore give me roughly 140Ah over the proposed 4 hour charge period and will put back in what I need.

 

I think it is better to err on the side of caution than to slowly kill your batteries over a matter of a few weeks.

[bottle]

I think 4 hours a day is way over when you start to monitor your charging tho and know how to read what the monitor is saying.

 

Is it?

 

Depends on battery bank size, usage and the ability to charge.

 

The only way to know is to monitor correctly, same hymn sheet.

[Johny London]

Hi and thanks for all the replies. I did not know that it was possible to kill new batteries so very very quickly. Since I got the boat I have been busy, cruising it across the country and doing jobs to it, as well as moving stuff aboard etc. Solar panels are high on my list, as is a generator, and some means of monitoring the batteries easily (I had a multimeter I could use for periodic checks). I just had not had the time to address these issues and thought that the batteries would be all right for a while at least, even if perhaps their over all longevity might get compromised.

So - bad news for me then! I'll try charging for longer, see if I can recover them for a bit, at least carry on using them until I get sorted with a smartguage and bmv1 - I had not heard of these before and have bought a couple of volt meter lcd panels to hook up to both domestic and starter batteries, was next job on list.

My engine has a separate 175 a/h alternator for the domestic bank. If I could get to a mains hook up I could use the sophisticated charging that the victron has to offer.

[chubby]

Am i on my own when if i consider it bonkers not to have solar panels these days . Unless you have aesthetic reasons for disliking them im often staggered to hear of liveaboard boats that don t have them .

I think i d be buggered without mine as it would drive me up the wall having to listen to my engine 4 hours a day .

With a bit of caution regarding power usage throughout the year they can make life aboard far more enjoyable . Yes theres an initial outlay and im not suggesting they re cheap but you can always create a system that allows for expansion later .

I think the OP would be wise to have look at solar charging because they just simply work wonders and will contribute massively i feel to protecting any further battery banks purchased .

Just my thoughts

PS i stand corrected re microwave usage

cheers

 

ETA : i think i was typing when uou replied OP

Edited August 29, 2016 by chubby

[Guest]

Am i on my own when if i consider it bonkers not to have solar panels these days . Unless you have aesthetic reasons for disliking them im often staggered to hear of liveaboard boats that don t have them .

I think i d be buggered without mine as it would drive me up the wall having to listen to my engine 4 hours a day .

With a bit of caution regarding power usage throughout the year they can make life aboard far more enjoyable . Yes theres an initial outlay and im not suggesting they re cheap but you can always create a system that allows for expansion later .

I think the OP would be wise to have look at solar charging because they just simply work wonders and will contribute massively i feel to preventing any further battery banks purchased .

Just my thoughts

PS i stand corrected re microwave usage

cheera

 

ETA : i think i was typing when uou replied OP

We have solar panels this year for the first time, and the difference has been amazing. Much less generator time when moored for longer periods. We haven't got an MPPT controller yet, so expect to see a further improvement when we get one.

I took the microwave off our boat. Cooking power may be 700W or so, but power consumed tended to be double the cooking power.

[Johny London]

Yes, since I got the boat I have been busy organising letting my place in London so that I could go live aboard - solar panels - I see them all the time and what with all the hot sun this year I feel I've really been missing out. Right now I'm planning/purchasing/fitting a kitchen - maybe it's not as important as solar but man am I sick of cooking on the floor with a two ring burner! I just haven't had time to do even the really high priority things and had just hoped that things would be ok for a bit. Did I mention the boat needs painting before the weather turns!? So far I managed to build a frame for my bed, so I'm comfy in my cabin and not throwing the mattress on the floor each night, I also got a settee, set up a temporary wardrobe, fitted the inverter, lights, 240 sockets, curtain poles and retainers (and partly finished curtains.

What a shame my new batteries have had it - just hope I can get some paint on before the rust sets in!

[Murflynn]

sorry to be pedantic, but you refer to 175a/h alternator and 0.52kW/h fridge.

 

these units should be independent of time, i.e. 175amp and 0.52kW.

 

it helps to understand the units as a starter, before you try to analyse your power usage and generating capacity.

[Paul C]

Hi All,

I picked up my newly built boat in May.

 

Right now I'm planning/purchasing/fitting a kitchen ................ Did I mention the boat needs painting before the weather turns!? So far I managed to build a frame for my bed, so I'm comfy in my cabin and not throwing the mattress on the floor each night, I also got a settee, set up a temporary wardrobe, fitted the inverter, lights, 240 sockets, curtain poles and retainers (and partly finished curtains.

What a shame my new batteries have had it - just hope I can get some paint on before the rust sets in!

 

I am guessing its a sailaway?

[Sea Dog]

The only thing on overnite (aside from the inverter) is

Some good advice above and I also would say you're under charging. However, since I don't think anyone else has mentioned it, don't leave your inverter on when you don't need to and certainly not just to keep a microwave clock alive overnight. An inverter uses power when idle and, although some (like my Mastervolt) have clever sensing modes to reduce consumption, they should be off whenever they're not really required.

 

Incidentally, we have a microwave but it only gets used when on shore supply or when the engine's running. Same with the coffee machine and the first lieutenant's hairdryer. When you get a way to measure current, you'll see that such seemingly low power 240v appliances put a big draw on the 12V side of the inverter - all 3 around 100 amps in my case. Some are OK with that draw for the short bursts involved (I'm more cautious), but you still have to put that usage back in your next charge.

 

Bottom line - turn the inverter off when not in use.

[Paul C]

Some good advice above and I also would say you're under charging. However, since I don't think anyone else has mentioned it, don't leave your inverter on when you don't need to and certainly not just to keep a microwave clock alive overnight. An inverter uses power when idle and, although some (like my Mastervolt) have clever sensing modes to reduce consumption, they should be off whenever they're not really required.

 

Incidentally, we have a microwave but it only gets used when on shore supply or when the engine's running. Same with the coffee machine and the first lieutenant's hairdryer. When you get a way to measure current, you'll see that such seemingly low power 240v appliances put a big draw on the 12V side of the inverter - all 3 around 100 amps in my case. Some are OK with that draw for the short bursts involved (I'm more cautious), but you still have to put that usage back in your next charge.

 

Bottom line - turn the inverter off when not in use.

 

I am not sure if the fridge is 230V and thus needs the inverter on 24/7.

[Sea Dog]

I am not sure if the fridge is 230V and thus needs the inverter on 24/7.

Yes, I see you might be reading it correctly Paul, in which case the inverter will be 'in use' 24/7 as you say and (like many) he'll have to suck up the extra drain of a full time inverter I guess. It's the advantage a 12V fridge brings which us why so many of us pay more to have one.

[Rickent]

This is what 175w of solar does to your batteries on a nice sunny day.

 

 

 

 

 

Edited to add , plus mppt controller.

Edited August 29, 2016 by Rickent

[Guest]

Hi All,

I picked up my newly built boat in May. It has 4 leisure batteries (100amp hour according to the d of c though they are tricky to get at) and I fitted a Victron 3000 inverter/charger. Only ever used the engine for generating. These days, I'm running the engine for three hours a day and by the next morning the batteries are down to like 11.7 volts or less. The only thing on overnite (aside from the inverter) is the fridge which supposedly takes .52kw/h, and the microwave with its digital clock. I have two or three hours of laptop in the evening for tv etc, and an hour or two of music through a 240v amp which is turned off (not standby) when not in use. Microwave some times for 5-10 mins. The batteries didn't used to go this flat, I can't think what I might be doing differently to cause this? When I first had the boat I was cruising a lot more, though I'm not quite sure when this apparent discharge started.

The fan belt squeaks for a minute when I start the engine but reads well over 14v when charging. A while after and they sit nice and high around 13v.

Surely not knackered the batteries already???

Using a similar charging regime as yours we managed to kill 5 new 110ah leisure batteries in around 18 months.

 

As others have said you are not charging them enough and the more you do not the quicker they die.

[Johny London]

Yes it was a sailaway - with additions - fully working bathroom and wc and all the wiring tails in.

I'm afraid a 240v fridge was all I had available to start with, so yes the inverter is on 24/7 and I know the self consumption of the inverter is over 1/2a. 12v fridge - yet another on my list of stuff to get and things to do. To be honest, If I'd gotten 18 months out of the first set of batteries, well by then everything else would have been in place (hopefully). Was hoping to buy a bit of time and I certainly can't do without a fridge on board

Again, without a microwave my food choices are limited to what I can boil up

[system 4-50]

Yes, since I got the boat I have been busy organising letting my place in London so that I could go live aboard - solar panels - I see them all the time and what with all the hot sun this year I feel I've really been missing out. Right now I'm planning/purchasing/fitting a kitchen - maybe it's not as important as solar but man am I sick of cooking on the floor with a two ring burner! I just haven't had time to do even the really high priority things and had just hoped that things would be ok for a bit. Did I mention the boat needs painting before the weather turns!? So far I managed to build a frame for my bed, so I'm comfy in my cabin and not throwing the mattress on the floor each night, I also got a settee, set up a temporary wardrobe, fitted the inverter, lights, 240 sockets, curtain poles and retainers (and partly finished curtains.

What a shame my new batteries have had it - just hope I can get some paint on before the rust sets in!

I am still on 1 ring so I know how you feel. And you are right, painting is still the highest priority.

[Arthur Brown]

batteries go flat! They go flat faster when you discharge them. The ONLY answer is to charge them sufficiently. Summer solar is usually all you will need, in the winter you will need much more engine running time plus probably 12 hours of cruising over the weekend. Or of course you could get a marina mooring with power bollards.