Our first year with lithium

[Laser310]

Interesting...

Is there much of a second hand market for new-ish AGM batteries?

 

[Laser310]

also.., it seems that what you are saying is that lithium makes better use of solar, because they accept the charge better/faster - right?

that would imply that with AGM, the limiting factor might not be the wattage of solar the boat has, but rather it could be the ability of the AGM bank to accept the charge.

am i understanding it correctly?

 

[GHA]

also.., it seems that what you are saying is that lithium makes better use of solar, because they accept the charge better/faster - right?

that would imply that with AGM, the limiting factor might not be the wattage of solar the boat has, but rather it could be the ability of the AGM bank to accept the charge.

am i understanding it correctly?

Yes, pretty much, lead acid will tail off current acceptance after about 80% soc and take ages to actually get back up to full charge, LiFePo4 just suck up all the power you give them all the way up to pretty much full so will get to full much earlier in the day than LA.
Mine went to float today just before 3pm then back into bulk with 20 minutes of a scrub of the keel & the compressor running.

 

[geem]

also.., it seems that what you are saying is that lithium makes better use of solar, because they accept the charge better/faster - right?

that would imply that with AGM, the limiting factor might not be the wattage of solar the boat has, but rather it could be the ability of the AGM bank to accept the charge.

am i understanding it correctly?

If you have sufficient solar to charge your lead batteries to float each day, then you will notice a large improvement when you flip to lithium. Most lead charge cycles need about 6 hours total combination of bulk and absorbtion. The absorbtion phase is at reduced amps as you are charging at constant voltage. This is where lithium makes a huge difference. You dontmneed to get to absorbtion every day or even every week. Partial state of charge is where lithium is happiest for long life

 

[gregcope]

Also the round trip efficiency of LifePo4 is high 90%. FLA is probably around 80%. So more of the Solar yield gets stored and more importantly returned.

 

[Neeves]

There is a repetitive theme that you need to keep the gas and maybe the generator for those days when the sun does not shine (or presumably you need to be careful of the stored amps (and harbour them). The other themes are when the sun shines relentlessly you waste amps and Lithium batteries are getting cheaper - so why not a bigger battery bank and dump the gas and the gen set. This caught my eye - we need got be more imaginative of our use of solar panels Balcony Solar Panels — Phaser Electrical. It appears balcony solar panels are big in Europe.

Or is this a step too far? and/or a sign the wind gen still has a place (SkyWind have just sold their 10,000th unit)

Is the all electric boat a dream? (ignoring the need for the diesel motor)

I have not looked but there must be a small electric oven. Or they do exist - but maybe not with the sophistication, nor a shrunken version of a 'standard' domestic electric oven.

When we lived in HK we had a small electric oven - just an element in the top. It was good enough to roast meat in, I think it might have had a rotisserie function, but we also had a bread maker and the only cake we made was cheese cake. (Too much sugar is unhealthy - or so I was told - and sugar is not really part of the Asian diet). This was 25-40 years ago - so oven technology must have improved (Motor homes?)

Geem - if you take the bread maker from home you'll still need another breadmaker, one at home, one on the boat - unless the bread maker commutes.

Jonathan

 

[Laser310]

Are many people switching to lithium doing the installation themselves?

It seems geem even built the batteries himself.

Is there trouble with insurers for do-it-yourself lithium installations?

 

[Laser310]

I have not looked but there must be a small electric oven. Or they do exist - but maybe not with the sophistication, nor a shrunken version of a 'standard' domestic electric oven.

I have crewed on some pretty large catamarans.

everything is electric..., no gas for anything except the barbecue. They had electric ovens, but it looked like they were regular on-land appliances; Bosch, for example.

Cats don't need gimbals.

The area that a 70ft cat can devote to solar panels is enormous.

They usually also have Watt and Sea hydrogenerators

 

[Neeves]

If you google, small electric ovens, you get lots of hits upto about A$600, if you go here Appliances Online

you need a much deeper wallet A$5,000!

And presumably your search will offer prices in your local currency

Jonathan

 

[Sea Change]

Are many people switching to lithium doing the installation themselves?

It seems geem even built the batteries himself.

Is there trouble with insurers for do-it-yourself lithium installations?

I did my installation myself. Bought the cells and the BMS direct from China.
My first battery cost £400, the second one slightly more because I was in the Caribbean by then and the shipping etc outweighed the drop in prices.
I was originally going to buy Trojan deep cycle batteries. My DIY lithium was half the cost up front for same useable capacity. And AGM are just silly money.

Building batteries isn't rocket science, if you're at all handy and can be trusted with a spanner you can probably do it. Loads of advice out there.

The batteries of course are only one part of the project. You've got to carefully consider the rest of the system- cables, fuses etc may need upgraded- and charging sources. This is where the real work goes.

Re insurance... can't answer that one, we gave up on insurance when we left Europe and were looking at paying 10% of our boat value per year... the joys of owning an old, cheap boat

 

[neil1967]

I installed 400AH of LiFEPO4 to replace 400AH of Trojan LA, together with the associated chargers etc. I currently don't have solar fitted (next project), but still the difference is amazing. With the Trojans, with the same 90A alternator, when I started the engine I would get about 30-40A charge for a few minutes before it dropped away. With the LiFEPO4, I get 60A charge which stays at that level until the batteries are charged. Furthermore, there is no significant self discharge - if I leave the boat for 2 months then when I return the batteries are still at 100%. I used 'drop in' replacement batteries, but still had to totally redesign the electrical system.

 

[Poecheng]

Are many people switching to lithium doing the installation themselves?

It seems geem even built the batteries himself.

Is there trouble with insurers for do-it-yourself lithium installations?

I discussed this with my insurers (Admiral) a week or so ago.
They are OK as long as
A) it is professionally installed (or presumably signed off by a professional) and
B) the BMS and other settings are appropriate for a lithium installation.

I expect they would want to see written evidence of it - not dissimilar to standing rigging where I have just sent them the invoice from the rigging company.

 

[vas]

I installed 400AH of LiFEPO4 to replace 400AH of Trojan LA, together with the associated chargers etc. I currently don't have solar fitted (next project), but still the difference is amazing. With the Trojans, with the same 90A alternator, when I started the engine I would get about 30-40A charge for a few minutes before it dropped away. With the LiFEPO4, I get 60A charge which stays at that level until the batteries are charged. Furthermore, there is no significant self discharge - if I leave the boat for 2 months then when I return the batteries are still at 100%. I used 'drop in' replacement batteries, but still had to totally redesign the electrical system.

I hope the 100% charge staying for a couple of months was an example and you dont keep them there for long! lifepo4 is happier half charged, that's where i try to keep them during winter and indeed they keep their charge just fine

 

[Trident]

I've had LiFePo for just over 4 years now on an all electric boat (no gas but diesel engines) and have 2100w of solar - we cook including using an electric over (microwave , grill, oven and airfare all in one) , we make water with a 100L water maker on an AC system, and then make it hot (60L of hot water today in the UK and two cooked meals and coffee maker and toaster) and when the sun went down just after the evening meal we were still at 95%

Over 4 years we have used the lithium every day like this and to date w have lost 0.8% of capacity - meaning that even if we say 90% capacity is time to change the batteries we should still get another 37 years out of them if progression is linear

I think we have charged from solar full time for 8 months of the year on average - the depths of winter are solar with shore power charger top up and everything run through the big Victron inverter so our winter bills have been much reduced too.

Meanwhile, next to our berth a new 48 foot Princess MoBo turned up - way north of £1M and each morning when the owner starts making breakfast his genny auto starts despite being on shore power. We have no genny, have only used the DCDC chargers when motoring for maybe 4 - 6 hours in 3 years because we just don't need them with solar and my total electric bills for living aboard over several winters in that time run to under £200 (winter heating is diesel of course)

 

[gregcope]

Are many people switching to lithium doing the installation themselves?

It seems geem even built the batteries himself.

Is there trouble with insurers for do-it-yourself lithium installations?

I built and installed my own.

My insurer (GJW) were fine with that. Others anecdotally have had issues with my approach.

 

[Neeves]

I've had LiFePo for just over 4 years now on an all electric boat (no gas but diesel engines) and have 2100w of solar - we cook including using an electric over (microwave , grill, oven and airfare all in one) , we make water with a 100L water maker on an AC system, and then make it hot (60L of hot water today in the UK and two cooked meals and coffee maker and toaster) and when the sun went down just after the evening meal we were still at 95%

Over 4 years we have used the lithium every day like this and to date w have lost 0.8% of capacity - meaning that even if we say 90% capacity is time to change the batteries we should still get another 37 years out of them if progression is linear

I think we have charged from solar full time for 8 months of the year on average - the depths of winter are solar with shore power charger top up and everything run through the big Victron inverter so our winter bills have been much reduced too.

Meanwhile, next to our berth a new 48 foot Princess MoBo turned up - way north of £1M and each morning when the owner starts making breakfast his genny auto starts despite being on shore power. We have no genny, have only used the DCDC chargers when motoring for maybe 4 - 6 hours in 3 years because we just don't need them with solar and my total electric bills for living aboard over several winters in that time run to under £200 (winter heating is diesel of course)

Any chance of a picture of your solar display - its the biggest issue for most (how, where to instal). I have 'feared' that unless the display is large, like yours, being sorely reliant on electric/solar is a dream. You only need 3-4 days overcast and you are running a smaller Lithium bank to 0%.

I may have missed it - what size of house bank?

Jonathan

 

[Trident]

Any chance of a picture of your solar display - its the biggest issue for most (how, where to instal). I have 'feared' that unless the display is large, like yours, being sorely reliant on electric/solar is a dream. You only need 3-4 days overcast and you are running a smaller Lithium bank to 0%.

I may have missed it - what size of house bank?

Jonathan

If its not raining tomorrow I'll take a photo for you

We have a 700 ah battery bank

I have the roof of my cockpit (Prout Quasar so much smaller than modern cats - the cockpit is 4m wide by 1.6m long) made of 4 x 320w 40v panels and then I have 5 x 175w flexi panels on the coach roof and deck. We have 4 separate MPPT controllers . I also have two more 175 flexi panels stored away to , in an emergency, be able to stick on the nets or point at the sun however needed but they never have been yet.

This means with combining series and parallel we end up with about 50 amps in this morning at about 10 am and by lunch time with intermittent cloud we had 85-90 amps going in for a few hours.

 

[geem]

......................

If its not raining tomorrow I'll take a photo for you

We have a 700 ah battery bank

I have the roof of my cockpit (Prout Quasar so much smaller than modern cats - the cockpit is 4m wide by 1.6m long) made of 4 x 320w 40v panels and then I have 5 x 175w flexi panels on the coach roof and deck. We have 4 separate MPPT controllers . I also have two more 175 flexi panels stored away to , in an emergency, be able to stick on the nets or point at the sun however needed but they never have been yet.

This means with combining series and parallel we end up with about 50 amps in this morning at about 10 am and by lunch time with intermittent cloud we had 85-90 amps going in for a few hours.

Our 920w of solar banged in 4.32kWh today. Another 600Wh from the wind turbine. You can't beat solar on a boat

 

[Neeves]

......................

Our 920w of solar banged in 4.32kWh today. Another 600Wh from the wind turbine. You can't beat solar on a boat

Its very unusual for anyone to show any interest in wind - which can be an invaluable resource.

Similarly hydro - but if you sit at anchor for weeks - hydro is obviously of no value

Your duo gen is the best answer to date - not based on any direct evidence from me

Jonathan

If its not raining tomorrow I'll take a photo for you

We have a 700 ah battery bank

I have the roof of my cockpit (Prout Quasar so much smaller than modern cats - the cockpit is 4m wide by 1.6m long) made of 4 x 320w 40v panels and then I have 5 x 175w flexi panels on the coach roof and deck. We have 4 separate MPPT controllers . I also have two more 175 flexi panels stored away to , in an emergency, be able to stick on the nets or point at the sun however needed but they never have been yet.

This means with combining series and parallel we end up with about 50 amps in this morning at about 10 am and by lunch time with intermittent cloud we had 85-90 amps going in for a few hours.

I was interested in the use of MPPT controllers. I understand how they work for one large panel or a cluster of panels all shaded similarly and all aligned similarly. I wonder about those temporary panels, panels attached to the stanchions and cantilevered out. Should you have a MPPT controller for each group of panels that are similarly located - or does it not matter?

MPPT controllers do not get much airing. You are the first person to highlight that you have 4 controllers.

That is a big battery bank. . More the size I had imagined one needed if you want to dispense with gas and the gen set.

Jonathan

 

[geem]

Its very unusual for anyone to show any interest in wind - which can be an invaluable resource.

Similarly hydro - but if you sit at anchor for weeks - hydro is obviously of no value

Your duo gen is the best answer to date - not based on any direct evidence from me

Jonathan


I was interested in the use of MPPT controllers. I understand how they work for one large panel or a cluster of panels all shaded similarly and all aligned similarly. I wonder about those temporary panels, panels attached to the stanchions and cantilevered out. Should you have a MPPT controller for each group of panels that are similarly located - or does it not matter?

MPPT controllers do not get much airing. You are the first person to highlight that you have 4 controllers.

That is a big battery bank. . More the size I had imagined one needed if you want to dispense with gas and the gen set.

Jonathan

We have 3 MPPT controllers. We group panels with the same shading characteristics. On the starboard guardrail we have a pair of series wired panels ( to suit a 24v system) on a dedicated MPPT. The port side has a similar series wired set up with its own MPPT. The roving 4x50w flexible panels are wired as 24v and have their own MPPT. The 3 MPPT controllers get their voltage information from the victron smart shunt via Bluetooth so regardless of where they are located in the wiring, they know the actual battery voltage rather than what they see at their terminals.