How long will we put up with this ancient technology?

Otter

Otter

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Last week we put in two new batteries. Each of them 105Ah and each needed a trolly to get them from the car to the boat. They were so heavy they needed two people to manhandle them aboard. Then they had to be got as low in the bilges are practicable. Then it was out with the crimper and wire to connect them.

Then I have the problem that I don't know how much power is in them and I can't even fill them up with power because they will only really accept about 90% of their capacity.

Oh, and I can't use more than half that capacity without damaging them.

So two hernias and three hours work to put about 100Ah in the boat - or enough for less than 24 hours use without charging (autopilot, lights, fridge, radio, plotter etc.) That's about 1.2kw of useable power.

Honestly why do we put up with 19th century technology like that?
 
1.2KW all day long , or for a specific duration ?

I guess that the batteries used in F1 racing are slightly more 'efficient', but the price is probaly 100 times more expensive per watt/minute.

Lead batteries are at the peak of their development asa result of refinement over 200 years or so. What is needed, I agree, is a step change in storage technology.
 
The technology is out there, just you won't like the price. The big move will be for electric cars where both weight and affordability will be key issues.
 
Lazy Kipper said:
.....So two hernias and three hours work to put about 100Ah in the boat - or enough for less than 24 hours use without charging (autopilot, lights, fridge, radio, plotter etc.) That's about 1.2kw of useable power.

Honestly why do we put up with 19th century technology like that?
Click to expand...

100 Ah * 12 V = 1.2 kW h. Enough to boil a few kettles full of water (if you have a 12V kettle)!

I've had a rare old struggle to find space for a second 85 Ah (claimed) battery in my (25') boat so I only have about 0.75 kW h available before the batteries start to suffer; and I have almost as much electrics as a normal 35' boat would have. The battery in my mobile 'phone probably has about twice the stored power/weight ratio of my lead-acid batteries, and is electrically more robust (ie more charge/discharge cycles, and can stand being flattened occasionally), but the cost of such a battery scaled up to boat size will tell you why they are not more generally used.
 
It's the colossal inefficiencies - in reality you get 90% of the capacity - say 95Ah but take it below 50% and you damage the battery - so you really get about 50Ah - that's about 1.5Ah useable per kilo weight!!!!!! Surely the cost of new gen batteries isn't quite as high as it seems because a battery than can repeatedly go down to 5% only needs to be 45% of the theoretical capacity of a lead acid ballast box.
 
Lithium ion batteries for boats are already out there. But they are still a year or two off being cost effective compared to lead acid. But basically the most basic reason that you are still struggling with yesterday's technology is because you didn't research Today's.
 
A 500 a/h Lithium Ion Battery in a housing similar to a car battery and only slightly larger that a truck sized battery is available from Chinese manufacturers for about £3.5k. Massive amounts of power for the same weight as a 135 a/h car battery. approx 40 kg for 500 a/h

one or two drawbacks apart from the price. 2000 charge cycle life but can be charged fast ( 100 amps or so no problem )

Once in a while they catch fire and the only solution would be to eject them into the ocean in a hurry although I don't know how you do it before they burnt through the bottom of the boat! :)

These guys are doing replacement liPoly batteries in smaller sizes, 10 of them would set you back a cool 3 grand and would deliver 240 a/h of which at least 95% would be useable.
 
Like everything in this world - you get what you pay for!
Top quality modern AGM batteries are far more efficient and will let you run them down to 20% charge. Cost - apprx 4 x lead-acid.
Lithium-ion are even better, and weigh less than half as much at lead-acid, but cost around £4k per 100Ah at present.
The technology is there, you just don't want to pay for it - and I don't blame you either!
 
Lazy Kipper said:
It's the colossal inefficiencies - in reality you get 90% of the capacity - say 95Ah but take it below 50% and you damage the battery - so you really get about 50Ah - that's about 1.5Ah useable per kilo weight!!!!!! Surely the cost of new gen batteries isn't quite as high as it seems because a battery than can repeatedly go down to 5% only needs to be 45% of the theoretical capacity of a lead acid ballast box.
Click to expand...

I looked at Lithium Ion batteries as they are now being used in electric cars so may be OK for domestic batteries, interestingly they prefer not to be discharged to low levels' it reduces their working life, they age losing capacity, they need built controls, and can go on fire if maltreated. Finally they have a high internal resistance which means they may not be suitable for engine starting, and perhaps winches and thrusters.

Here is a 100Ah battery, probably not yet cost effective on the basis of usable AH per £

http://www.es-store.co.uk/super-b-lithium-ion-traction-batteries/BAT-LI-SB-E-13.2V-100AH.html
 
Well, if you don't like the "19th cent. technology" go and buy a better one. As you said, don't put up with it.

But then you'll soon find that unless you yourself can do what modern technology has been unable to achieve and invent something better you're going to have a long search.

Sure, you can buy NiCad or other exotics, but if you're minded to beef about lead-acid you'll beef ten times as loud at the cost of those.

Anyway, the "19th cent. technology" you are so keen to disparage is in reality the 21st century state of the art (because if you had even 30yr old technology batteries you'd notice a considerable difference in performance) and as good as you can reasonably get.

If you want space technology as in fuel cells get a NASA budget. Simples.

Or get by without unreasonable electric demands, or get a boat big enough for submarine batteries, or get a genny, or...or...or....

As with everything in life here isn't an all round solution - you're going to have to compromise for the forseeable future and that almost certainly involves a very 19th cent. philosophy, namely economy of usage. I know, an incomprehensibly old fashioned concept to some these days. Welcome to boating.
 
It comes down to market size doesn't it. I take the point that there have in fact been improvements in Lead Acid Batteries, but it is also true that the spectacular advance in mobile phone batteries, (most of us have I'm sure seen those clips from the 1980s when the presenter proudly demonstrates his new mobile phone connected to a battery that needs an assistant to carry it around) haven't been replicated in batteries which can start your engine.

Presumably the growth in usage of electric cars and the need for lighter batteries will filter down to us eventually.
 
They work for me, what are you trying to drive? we had surplus power when cruising from two 120Ah, a towed genny and a wind genny when anchored. Never needed to run the engine for power or plug into shore power and that was living aboard running nav lights and an ST6000 probably over 20 hours a day when sailing.
 
If you ever (and perhaps you did) tried to start an ageing diesel Ferguson tractor with two 6-volt batteries on a frosty morning in the 1970's or earlier, I think you'd agree that lead-acid battery technology has in fact come quite a long way! ;)

dk said:
Top quality modern AGM batteries are far more efficient and will let you run them down to 20% charge. Cost - apprx 4 x lead-acid.
Click to expand...
Interesting - I was under the impression that while AGM are extremely good at not self-discharging when un-used, and can deliver very high cranking currents for their size (hence popular for performance cars), one of the disadvantages was that they didn't like to be deeply discharged. I may be mis-informed though. I have two 100AH ones in my shed that came from a large IT server backup system; I keep meaning to fit them to the boat - I guess when I do I'll find out for myself. Did you have a specific brand in mind that claim to go down to 20%?
 
Nothing at 60 like a feel good thread-I can carry my high top 110 ah lead acid batteries and get them up a ladder whilst ashore. I can even just about manage a very akward pull out of the battery box.
I do try to be sensible-two years ago I tried using my dingy davit to lower a battery the 15 or so feet down to the ground.I miss tied it or something and saw £100 of battery smashed into bits!
I have no need to do this with my main starter battery which is on permanent trickle charge from a very small solar panel-always on full charge and vnever overcharged despite no management unit.
 
I would dearly like to change to Lifeypo (Lithium) batteries and have identified the cells I could use. However the following problems have prevented my change

I would need similar technology starting battery and they are very much in their infancy.

Use of Lithium cells demands a battery management system, and cell balancing systems - these are not much better than breadboard designs for electric cars, and in my opinion not sufficiently robust for marine use.

I would need a special solar controller, battery charger, and alternator controller suitable for lithium as the staged approach does not work for lithium cells.

lithium also needs a different way of demanding power from charging systems - not yet available.

The alternative is the mastervolt batteries at 5000 GBP each, which are supposed to work - but I suspect that you need the other bits as well.


So - the batteries now exist and are becomeing cost viable. The extra bits needed to be able to use the lithium batteries are still in their infancy.
 
Lazy Kipper said:
Honestly why do we put up with 19th century technology like that?
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Why do you? There are more modern alternatives to lead acid batteries. All you need to do is to put your hand in your pocket. But presumably, thats why you chose the batteries you did. Cheap - the batteries not you.
 
nimbusgb said:
Once in a while they catch fire and the only solution would be to eject them into the ocean in a hurry although I don't know how you do it before they burnt through the bottom of the boat! :)
Click to expand...

You think throwing a huge block of lithium into water is a good plan? I thought everyone had seen that experiment at school :eek:
 
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