PaulRainbow
Well-Known Member
You're right, plain ole VSR will do.
Fitting a LifePO4 battery seems like a huge waste of money. A simple AGM battery and a couple of solar panels on the roof would cost much less and work better.
Li Ion leisure battery
- Thread starter fisherman
- Start date
You're right, plain ole VSR will do.
Fitting a LifePO4 battery seems like a huge waste of money. A simple AGM battery and a couple of solar panels on the roof would cost much less and work better.
rszemeti
Well-Known Member
Real world experience in the "off grid living" community would suggest otherwise.
Lead Acid has the basic problem of it doesnt like being discharged. Regularly draw down more than 50% of the charge and the battery is not going to last. Trying to argue that Lead Acid (in any of it's many guises) works better than LiFe PO4 is a fools errand, the performance of LiFePO4 is just too good to argue against.
At current prices, it certainly is a very expensive option, and you may well be right that to many people, the money could be better spent elsewhere. I certainly would not pay the daft prices being asked at the moment, but I do know people who have built up significant sized LiFe battery systems for realtively little cost, and the performance is stunning. There are various groups on the web dedicated to this stuff, searching out supplies of defunct cells and strapping them together in various arrays ... it can certainly be done for a lot less than the daft prices currntly advertised, if you are prepared to get your hands dirty.
Lead Acid has the basic problem of it doesnt like being discharged. Regularly draw down more than 50% of the charge and the battery is not going to last. Trying to argue that Lead Acid (in any of it's many guises) works better than LiFe PO4 is a fools errand, the performance of LiFePO4 is just too good to argue against.
At current prices, it certainly is a very expensive option, and you may well be right that to many people, the money could be better spent elsewhere. I certainly would not pay the daft prices being asked at the moment, but I do know people who have built up significant sized LiFe battery systems for realtively little cost, and the performance is stunning. There are various groups on the web dedicated to this stuff, searching out supplies of defunct cells and strapping them together in various arrays ... it can certainly be done for a lot less than the daft prices currntly advertised, if you are prepared to get your hands dirty.
PaulRainbow
Well-Known Member
What would i know, i'm barely onboard
It's not the batteries that work better, it's the solar. Fit the right solar and you only need to store enough energy to see you through the night, plus maybe a day if it's cloudy.
You could live on a 35' yacht with just 390ah of lead acid batteries and some solar panels but the OP is only talking about a modest campervan.
Ningaloo
Well-Known Member
I wonder if anyone has any experience of carbon foam batteries?
http://www.coastalclimatecontrol.co...OC-marine-battery/p/95699247/category=2582370
I currently have 2x160Ah AGM but they have started to deteriorate (after 4 seasons) and I'm pondering on replacement options.
http://www.coastalclimatecontrol.co...OC-marine-battery/p/95699247/category=2582370
I currently have 2x160Ah AGM but they have started to deteriorate (after 4 seasons) and I'm pondering on replacement options.
Stemar
Well-Known Member
No experience of them but, from the ad, they look to be a variation on a theme of lead acid.
Provided you don't run them down too far, I still reckon that plain vanilla lead acid gives the best return in amp hours per cycle per £.
Provided you don't run them down too far, I still reckon that plain vanilla lead acid gives the best return in amp hours per cycle per £.
macd
Well-Known Member
Indeed. Throw them off your boat...along with your laptops, kitchen scales, mobile phones...
And on a related subject, what about the fire/explosion risk with lead-acid batteries? People seem fond of comparing the two as though it's zero. It's not.
Seajet
...
Actually I have a breather tube from my battery to a ventilator, I've seen the results of a battery explosion and it didn't look much fun - ask submariners.
fisherman
Well-Known Member
If we used lead acid the battery compartment will be sealed inside and vented to outside. Not an option currently.
pvb
Well-Known Member
If you used AGM batteries, ventilation would be less of an issue.
PaulRainbow
Well-Known Member
Oh dear, i'm sitting on the port side sofa, right on top of 4 large batteries, i'm doomed !
Seajet
...
Have a camera with a motor drive strapped around your neck at all times, if the worst happens keep the shutter release pressed and you should get some great photo's of your boat as you go into orbit.
PaulRainbow
Well-Known Member
Have a camera with a motor drive strapped around your neck at all times, if the worst happens keep the shutter release pressed and you should get some great photo's of your boat as you go into orbit.
Actually, i'm double doomed, my van battery is in the cab.
But, there are lots of other vans and cars with batteries in the cabin.
lw395
Well-Known Member
My laptop runs for quite a few hours on its battery. A spare battery for it is about £60.
It's about 7Ah.
A Li-ion battery to fit my bike costs more and is only 3Ah!
Back in the last century, at one point I had some laptops with removable battery packs and separate chargers, so you could charge spare batteries while they were out of the machine. Not seen anything like that for a while?
Sooner or later, all hippy wagons seem to resort to a suitcase generator. You might as well design around that in the first place?
It's about 7Ah.
A Li-ion battery to fit my bike costs more and is only 3Ah!
Back in the last century, at one point I had some laptops with removable battery packs and separate chargers, so you could charge spare batteries while they were out of the machine. Not seen anything like that for a while?
Sooner or later, all hippy wagons seem to resort to a suitcase generator. You might as well design around that in the first place?
Monique
Well-Known Member
Seajet has a very valid point; I once had a NiCad battery go in thermal runaway in an aircraft at high altitude.
We did an emergency landing; definitely a brown trouser potential. I like my choice of "lead crystal" as they are not vented (apparently no gas is produced)
We did an emergency landing; definitely a brown trouser potential. I like my choice of "lead crystal" as they are not vented (apparently no gas is produced)
Seajet
...
Not a Dreamliner by any chance ?
Achosenman
Well-Known Member
The B787 uses Lithium Ion batteries. The issue of thermal runaway at the end of the charge cycle was cured...
All the aircraft now have an explosion proof, stainless steel and concrete battery enclosure. This is vented to the outside of the aircraft. I have years of flying on the type. I never had an issue with a battery, but I was reassured when I inspected the fix.
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crisjones
Well-Known Member
Lithium Ion Battery is a pretty generic description of any Lithium battery is does not describe the actual chemistry of the battery - so saying the B787 uses Lithium Ion batteries does not accurately describe the battery and does not differentiate from any other type of lithium battery.
Even most scientific papers and reports on the Dreamliner battery problems describe them as Lithium Ion batteries so it is not surprising that the term is in general use.
The batteries on the Dreamliner are Lithium Cobalt Oxide (LiCoO2) chemistry, high energy density but prone to thermal runaway if not properly managed. Almost all Lithium batteries that are likely to be fitted on yachts or RV's are going to be Lithium Iron Phosphate (LiFePo4) chemistry. This is the safest of all the Lithium battery chemistries and I would consider it to be actually safer than Lead Acid for yacht and RV useage.
Both types of batteries are Lithium Ion so using that term to describe a lithium battery does not actually tell you much.
There are quite a few other Lithium battery chemistries in general use and a google search for "lithium battery type comparison" will give you plenty of info if you are interested.
Interesting that Boeing's "Fix" for the battery problem - enclosing it in a stainless steel and concrete enclosure together with external venting - totally negated the weight savings that were the reason for choosing the LiCoO2 battery in the first place!
Even most scientific papers and reports on the Dreamliner battery problems describe them as Lithium Ion batteries so it is not surprising that the term is in general use.
The batteries on the Dreamliner are Lithium Cobalt Oxide (LiCoO2) chemistry, high energy density but prone to thermal runaway if not properly managed. Almost all Lithium batteries that are likely to be fitted on yachts or RV's are going to be Lithium Iron Phosphate (LiFePo4) chemistry. This is the safest of all the Lithium battery chemistries and I would consider it to be actually safer than Lead Acid for yacht and RV useage.
Both types of batteries are Lithium Ion so using that term to describe a lithium battery does not actually tell you much.
There are quite a few other Lithium battery chemistries in general use and a google search for "lithium battery type comparison" will give you plenty of info if you are interested.
Interesting that Boeing's "Fix" for the battery problem - enclosing it in a stainless steel and concrete enclosure together with external venting - totally negated the weight savings that were the reason for choosing the LiCoO2 battery in the first place!
Achosenman
Well-Known Member
Very interesting, but way beyond my need to know threshold as "driver, air-frames"
Thermal runaway was something we became aware of just prior to the introduction of the B787. At annual refresher training they showed us a horror film of a laptop battery on fire. It was the most alarming thing I have seen. Especially when you consider the temps involved, the difficulty in quenching/controlling it and the fact that you might be at FL430.
I noticed a lot of colleagues surreptitiously removing laptop batteries when not in use... including me.
Stemar
Well-Known Member
What makes lead acid batteries go bang is hydrogen. Being very much lighter than air, it will disperse very quickly in any sort of ventilated space, even an unsealed one. I'd never say it's impossible to blow up your boat with it, but you'd really have to work at it. You're in far more danger from that Sunsail boat half a mile away
GHA
Well-Known Member
Firefly have been getting rave reviews from testing by a few LX engineers stateside , so far sounds like they do what it says on the tin with tests which would trash ordinary lead acid. Have a search on cruisersforums. Major downside for a cruising boat with the more standard lead acid is getting them back up to 100% state of charge often, necessary to get a good lifespan. Which is where LiFepo4 & firefly win.