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Lithium (LiFePO4) batteries

Hi Grant,

Any progress on this topic? I am also looking into this option from the same seller.

My current concerns are:
Using it as a leisure battery and charging it not only with solar but also with the alternator. I believe the alternator puts out to much current for the packs. Also I read that these batteries don't care to be fully loaded, so to be safe it might be better to always set all the load levels a bit lower to increase longevity. When you would charge them via the alternator I also read that as they can charge so fast it might put a big strain on the alternator, making it push at 100 % for to long which would then lead to premature failure of the alternator.

When looking at the battery price I am willing to put of the money. Not sure if I would spend the money for a BMS (250 EUR on a 600 EUR battery in my case). However I do get a bit worried when I look at the additionals to install to have it work. When looking at the Victron website I see so many required installs to make this work that all these extras easily add up to more then the batteries cost.

I have however also seen a charger from Australia for LiFePO4 from Redarc. This charger is pricy, but turns 9 to 32 volts into 12 volts and can act as MPPT for you solar as well, which makes it a money saver in same way.

Looking forward to hear what you have done!

Unfortunately no progress yet but I am getting close to buying this:
https://www.ev-power.eu/en/By-Brand....html?cur=1&listtype=search&searchparam=yacht

I've bought a 140amp alternator and would love to be able to charge these at 100amp (.5c) or 80amp as a minimum. I'm unsure what voltage I will get by the time it reaches the rear of my trailer where the batteries will be so to regulate this and to be able to control the amperage going in i've purchased two of these:

https://www.ebay.co.uk/itm/1200W-20...-OUT-12-70V-/272387871223?hash=item3f6b9511f7

It says these can be run in parallel to increase amperage so if this works i'll put more of these in to get the desired amps.

I think the BMS is the critical component for such an expensive battery, especially as the one in the system linked above is able to have relays to that will disconnect the charge and discharge circuits separately.

I have seen the redarc controller but it's max charge current was only 30amp so it negates for me the biggest advantage of lithium which is it's super fast charging ability.
 
Lots of big expo trucks use them these days - UNICAT's etc. I also know a few other people are looking at them... however at the moment just looking.
 
Lots of big expo trucks use them these days - UNICAT's etc. I also know a few other people are looking at them... however at the moment just looking.

It is the problem - at the lower end of the spectrum where you only need 100 or 200 amps there isn't a lot of knowledge about. The big expensive installations use Victron BMS systems ... but they are way too pricey for a camp trailer (starting point is at least £3k.) The consumer end of the charger market still seems to be stuck at lead acid/AGM battery charge rates. A good (or any) fast DC to DC charger for not crazy amounts of money (less than £600) doesn't seem to exist. Given they are a more simple than other leisure battery chargers it does mystify me a bit ... but I guess we just have to wait for this market segment to mature more.
 
I have seen the redarc controller but it's max charge current was only 30amp so it negates for me the biggest advantage of lithium which is it's super fast charging ability.

that may not be as bad as you think mate. I've got a redarc unit connected to a 100Ah lithium battery and the rate of charge is pretty impressive, by which I mean 20%DOD to 100% in about 1.5 - 2 hours.

One thing you might want to keep in mind. All LiFePO4 batteries have an internal charge controller which dynamically manages charge and draw from each cell based on their individual state of charge. Getting a matched controller (tested and approved by the battery manufacture) will go a long way to optimising charging and minimising the risk of fire through over charging.

My redarc was recommended for use with the battery and they have been pretty happy together since the summer :)
 
that may not be as bad as you think mate. I've got a redarc unit connected to a 100Ah lithium battery and the rate of charge is pretty impressive, by which I mean 20%DOD to 100% in about 1.5 - 2 hours.

One thing you might want to keep in mind. All LiFePO4 batteries have an internal charge controller which dynamically manages charge and draw from each cell based on their individual state of charge. Getting a matched controller (tested and approved by the battery manufacture) will go a long way to optimising charging and minimising the risk of fire through over charging.

My redarc was recommended for use with the battery and they have been pretty happy together since the summer :)

2 hrs is pretty good really! I still want more though ... especially since I want 200 amps which would take that up to 4 hours. The Winston cells above don't have any charge controller at all they are just the raw cell so to speak. LiFePO4 batteries shouldn't catch fire at all even if massively over charged.

Is this the sort of controller you have? https://www.redarc.com.au/themanager30
 
Is this the sort of controller you have? [URL said:


That is exactly the one I have.. coupled with a Revolution Power battery if that helps at all.

Out of curiosity, what exactly are you running to warrant 200Ah which would be 160Ah of usable juice?
 
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That is exactly the one I have.. coupled with a Revolution Power battery if that helps at all.

Out of curiosity, what exactly are you running to warrant 200Ah which would be 160Ah of usable juice?

Nothing crazy I just want to be able to not worry about charging for at least 5 days when stopped. So most of it will be used by the dual zone fridge and lighting.
 
LiFePO4 batteries shouldn't catch fire at all even if massively over charged.

Are you sure about that bud? The chemistry sure makes them safer but if you drive them hard enough for long enough I'm sure they still pose a self sustaining ignition risk. Admittedly I haven't looked into your specific batteries in any great detail so could be completly wrong.

That was one of the reasons I went with the redarc which monitors a number of battery vitals including temperature and state of charge. (as I understand it, when the battery is near fully charged is when it is at its most dangerous as once its full anything you push in is dissipated as heat).
 
Are you sure about that bud? The chemistry sure makes them safer but if you drive them hard enough for long enough I'm sure they still pose a self sustaining ignition risk. Admittedly I haven't looked into your specific batteries in any great detail so could be completly wrong.

That was one of the reasons I went with the redarc which monitors a number of battery vitals including temperature and state of charge. (as I understand it, when the battery is near fully charged is when it is at its most dangerous as once its full anything you push in is dissipated as heat).

Well I wouldn't stake my life on it so only as sure as you can be from reading about it online. You tube at least doesn't have any videos of them catching fire in a complete short circuit. There is a few interesting videos here ... but they don't prove anything 100%. Careful not be confused with the lipo chemistries as they are highly volatile.

https://www.google.co.uk/search?biw.....0...1.1.64.psy-ab..5.1.119....0.jXl_ME8xaSU
 
Unfortunately no progress yet but I am getting close to buying this:
https://www.ev-power.eu/en/By-Brand....html?cur=1&listtype=search&searchparam=yacht

I've bought a 140amp alternator and would love to be able to charge these at 100amp (.5c) or 80amp as a minimum. I'm unsure what voltage I will get by the time it reaches the rear of my trailer where the batteries will be so to regulate this and to be able to control the amperage going in i've purchased two of these:

https://www.ebay.co.uk/itm/1200W-20...-OUT-12-70V-/272387871223?hash=item3f6b9511f7

It says these can be run in parallel to increase amperage so if this works i'll put more of these in to get the desired amps.

I think the BMS is the critical component for such an expensive battery, especially as the one in the system linked above is able to have relays to that will disconnect the charge and discharge circuits separately.

I have seen the redarc controller but it's max charge current was only 30amp so it negates for me the biggest advantage of lithium which is it's super fast charging ability.

You don't think that charge at this high amperage for a long time will put a lot of strain on the alternator, even such a big one as yours?

Also are you so far just planning on connecting it directly or are you using a charger for it? The question is, if you have a good BMS do you actually even need a charger, as I would imagine the BMS cuts of the charging when rates get to high!?
 
You don't think that charge at this high amperage for a long time will put a lot of strain on the alternator, even such a big one as yours?

Also are you so far just planning on connecting it directly or are you using a charger for it? The question is, if you have a good BMS do you actually even need a charger, as I would imagine the BMS cuts of the charging when rates get to high!?

I'm prepared to sacrifice the alternator for this. The one I have currently is reasonably low cost so I expect it to die at some point. If it get more than a year out of it I will be happy. If everything proves successful and it dies I will get a truly heavy duty one.

With regards to the BMS and a battery charger i'm saying yes. The alternator at most is only going to output 14.8 volts (more likely 14.4) and I suspect being routed back to the trailer I will se eat least a .4v drop. The batteries I'm looking at above will need 15.2v to charge just below the 100% mark.
 
I finally have this setup in a position where I’m happy with it. It’s taken a lot of work and experimentation to get charge rates I’m happy with.

The biggest change I’ve had tk make is using two victron 12 to 24v converters. Each of these is rated at 20amps on the 24v side. They are putting a big strain on the alternator so I’ve yet to see how long this will last - but it has been outputting over 100amps (my clip on meter only goes to 100)

The highest charge rate I’ve seen is 970w or 36amps at 24volts to get this any higher I would need to upgrade the alternator and add additional step up converters.
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BFDFC2A3-6CE0-4ADB-ACA7-2062F893F01F.png
 
A bit late to the fold but LifePo4 batteries are supposed to be the safest variant of Lithium cell in addition to being the most durable. I bought 4 cells to make a battery pack for portable radio use. 15ah, 3.2v per cell with 3c max charge rate and 5c max continueous or 10c pulse discharge (30 sec) rate. Also needed some sort of BMS unit or balance charger and opted for the latter. The current these cells can deliver if shorted really belies their size.


58D2AE8A-37EE-4954-9813-C9210F999BEE.jpeg
 
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I've been running a 120AH lifepo4 for just under a year now (Yet another 80 build thread - [Leaving Land Cruiser Club]) and the only issues with it is, do not charge it when temperatures are below freezing it will damage the battery, this can easy fixed using a smart relay and a Victron temp sensor. My battery charges at 40amps but that's because I've limited it to that in my setup due to battery sizing / temp. I'm going to add another 120AH just because that way I can run my fridge and everything for two weeks without moving or solar working, give me so much head room for getting a larger fridge etc.
 
I've been running a 120AH lifepo4 for just under a year now (Yet another 80 build thread - [Leaving Land Cruiser Club]) and the only issues with it is, do not charge it when temperatures are below freezing it will damage the battery, this can easy fixed using a smart relay and a Victron temp sensor. My battery charges at 40amps but that's because I've limited it to that in my setup due to battery sizing / temp. I'm going to add another 120AH just because that way I can run my fridge and everything for two weeks without moving or solar working, give me so much head room for getting a larger fridge etc.

Shouldn’t you be able to quite comfortably charge that at .5c (or60 amps )?

I’ve read a blog on ev-powers website (where I bought my cells) that says they can charge at well below freezing but also didn’t offer anything to really back it up on their product info pages. I won’t be taking this risk anytime soon though!

what battery and fridge combination do you have? I would also love to know what your charging setup is. In warm weather I get 4 days max out of100amps 24v with my 65litre snow master fridge.
 
A bit late to the fold but LifePo4 batteries are supposed to be the safest variant of Lithium cell in addition to being the most durable. I bought 4 cells to make a battery pack for portable radio use. 15ah, 3.2v per cell with 3c max charge rate and 5c max continueous or 10c pulse discharge (30 sec) rate. Also needed some sort of BMS unit or balance charger and opted for the latter. The current these cells can deliver if shorted really belies their size.


View attachment 165127

Not really late - look at the date of the origins post
 
My charging setup is a Redarc charger which maxes out at 40amps, I have Victron battery monitor, I sized the Redarc like that because if I charged them at >35 amps you can actually feel the batteries getting toasty. Plus 120 / 40 is 3 hours and that's fast enough for me, I never take them below 50% anyway.
My fridge is a 15l fridge (tiny but was just for me Bearmach Fridge-Freezers - [Leaving Land Cruiser Club]) although this is now going to change with a little one and the wife wanting to go camping more and in the summer it was pulling 19.2 ahs per day at 3c, so roughly 6 days max, before I have to charge the battery, but now I've got 150W solar panel, I'm always full at the end of the day.
The chemistry in lifepo4 will not allow them to charge below freezing without them damaging themselves, the battery must have a heating element in them otherwise I can't see how they can say you can charge them below freezing. The batteries I used have just dropped in price again US $423.0 10% OFF|4PCS 3.2V 120Ah LiFePO4 Long LifeCycles 3500 Times Max 3C For 12V Solar Energy Storage Battery pack|Rechargeable Batteries| | - AliExpress - [Leaving Land Cruiser Club] and if you look at the datasheet they say charge temp 0 - 45c.
 
This is what Relion say about charging my batteries at below freezing, but not to sure how you can do it. TBH cold weather charging is not a problem for me as the truck is heated so if I'm using it in the winter the heating will be on, only issue would have is moving it when it is cold around the yard and all I do is turn the dc to dc charger off.
Charging Temperature
LiFePO4 batteries can safely charge between -20°C to 55°C (-4°F to 131°F). However, at temperatures below 0°C (32°F) the charge current must be reduced, until the temperature is >0oC (32oF), as follows:
1. 0°Cto-10°C(32°Fto14°F)chargeat0.1C(10%ofthebatterycapacity)
2. -10°C to -20°C (14°F to -4°F) charge at 0.05C (5% of the battery capacity)
LiFePO4 batteries do not require temperature compensation for voltage when charging at hot or cold temperatures.
All Relion LiFePO4 come with a BMS that protects the battery from over-temperature. If the BMS disconnects due to high temperature, wait until the temperature reduces and the BMS reconnects the battery circuit before using or charging the battery. Please refer to your battery data sheet for the BMS high temperature cut-off value.
 
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It’s hard to find concrete information on but my bms Comes preconfigured to -20c for the min temp. They are rated at -45 for discharge.
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