Any thoughts, advice or experience of lithium ion battery systems please?

[Tranona]

The place to start, and one often overlooked, is to do an accurate energy audit to assess how much you use.

Step two is to think about how long you want to stay off grid.

Only after doing those, can you come up with realistic energy storage solutions without over complicating things unnecessarily, and to assess if you need supplementary charging equipment.

+ one. People, particularly those selling lithium tend to concentrate of the properties of the product and dissing the current products with carefully constructed "comparison" without asking the basic questions about whether these properties are of value to the user. The pros and cons are well summarised in post#6. However, there is a sort of snakes and ladders continuum from basic lead acid up to lithium. The continuum is basically in terms of usable energy capacity and potential life usually expressed in terms of cycle life. Along the continuum (going up the ladder) you hit spots where the snakes get you and to go up the ladder again you need to make major changes, usually in your generation capacity and method.

For people using basic LA there are big gains to be made, particularly in life (both absolute and in relation to cost) with minimal changes elsewhere. That is good steps up the ladder and little interference from the snakes. The vast majority of leisure boating needs (and many liveaboard) can be met by AGMs and it is only when you get to high usage in terms of cycles or you want to take advantage of the enhanced properties by going electric (for example for cooking) that building a lithium system becomes attractive. Not just changing the storage (battery) type but the management system and means of generation.

If you work through this sort of analysis it quickly becomes clear that for the typical weekend user (maybe 50 days a year plus long holidays) with good generating capacity (particularly shorepower) lithium is simply not cost effective, as you can't take advantage of the properties it offers. With a well sized bank and good management of charging it is quite possible to get 10-15 years out of AGMs, roughly twice what you might get from basic LA for about 50% more (or less) initial cost. The premium for AGMs has dropped dramatically in recent years because of the switch in the automotive market.

 

[Outinthedinghy]

My solar panel man is a big advocate of AGM. He lives in a house and has a great big bank of Yuasa AGM. Ex telecom standby batteries. Good value for money. Well looked after with plenty of solar and quality controllers.

The AGM do work. Also as mentioned the stop-start car batteries are AGM so prices can be attractive.


Lithium batteries definitely make sense if you are going for electric prop or high consumers as the blocks are lighter than lead acids which can be a significant factor on smaller boats. Also if you were to be running an electric prop then you will be doing a lot of cycles on the batteries.

Gel are another good old school chemistry.

It will be interesting to see how the prices go. If there are problems with raw materials the prices might not come down that quickly.

Tesla seem to be having some issues with Lithium supply.

Solar has come down a lot since I bought my first 75w 12v panel back in 1995 for £375.

 

[Tranona]

I had a 385Ah (3*95ah stop start AGMs) house bank on my last (sailing) boat and with an average usage of around 80 a day would be able to do 2-3 days without any charging, although typically would put about 30-40% of that back through motoring on each passage. No solar. So after 4 or 5 days definitely in need of shorepower.

Problem for a lot of people is they underestimate consumption and do not leave their boats fully charged before starting another set of cycles. So instead of using 100% down to say 50% they use 80 down to 30. Capacity reduces with age, so not surprising that many batteries fail before they should. Ok if you have shorepower to plug in which should get even a big bank up to float within a day or so, or if on a mooring a solar panel to trickle charge.

My Morgan is still on its original AGM Red Flash battery after 19 years and its usage cycle is not unlike a boat - short periods of feverish activity followed by long periods doing nothing. plug in the trickle charger if not used for say 3 weeks. Never failed to start.

 

[ashtead]

I am not currently convinced for my sailing that the price merits but if I was going off grid crossing to say Bonaire etc I might invest but otherwise it seems a lot better ways to invest in boat kit.

 

[nfluester]

for general use a good quality AGM or Lead carbon would be a big upgrade from a traditional flooded lead acid truck battery where lithium really makes sense is where you want to run high current loads or not have to worry about.

we used to be like apollo 13 trying to conserve every amp and living like hermits were as now we run the immersion heater every morning for hot shower before we set off, electric cooking and a Nespresso.

we used to use a petrol suitcase generator which was very anti social on the thames and for us the Lithiums was an alternative to this or paying out for an installed generator

 

[nfluester]

for general use a good quality AGM or Lead carbon would be a big upgrade from a traditional flooded lead acid truck battery where lithium really makes sense is where you want to run high current loads, big inverters or not have to worry about power useage.

we used to be like apollo 13 trying to conserve every amp and living like hermits were as now we run the immersion heater every morning for hot shower before we set off, electric cooking and a Nespresso.

we used to use a petrol suitcase generator which was very anti social on the Thames and for us the Lithiums was an alternative to this or paying out for an installed generator