LiFePO4 - slowly prices are coming down

[veletron]

Slowly but surely, these continue to come down in price.

 

100AH now available for £900: http://www.alpha-batteries.co.uk/12v-100ah-relion-lithium-battery/

 

Aliexpress has some 100AH LiFePO4 batteries direct from China for £612. I don't wanna be the Guiana-pig with these though!

 

Will be nice to get a lead-acid equivalent of 170AH in a package that weighs just 13KG, and does 3000+ cycles.

 

I predict prices under £500 for that 100AH Relion by this time next year which will make their selection cost-effective for many users over lead-acid.

 

Nigel

[aandncaravan]

The publicity claims for LiFePO4 batteries say they don't always require a specialised charger. 'Any Lead acid charger will do'. Yet a Motorhome fitted with a Sargent EC325/EC328 will destroy a LiFePO4 in a glittering display to rival the best fireworks. Installed badly these can be seriously hazardous.

 

The actual publicity for the battery in the above link claims, "Can be charged with conventional chargers".

Yet a 13.5v Motorhome charger would take forever to charge up a battery like this and most likely massively shorten it's life. The 17v output from a Sargent EC328 will destroy a £1,000 battery.

 

Note also that the claims for battery performance assume that the charger IS an optimised, specialised unit. If you do use 'just any old Lead battery charger', you won't get any where near the claimed cycle life. Obviously a 5amp charger isn't going to deliver the ability to be 'charged 2 - 3 times faster'.

 

Many Continental built vans have power units like the Schaudt EBL 220 that will not work properly if the Schaudt box does not control all the power going into/out of the battery.

 

 

LiFePO4 often come as a complete 'Pack' with a charger and electronics (like EZA 130Ah) to both limit charging and power draw, to prevent battery damage. Run a LiFePO4 down flat and you will have a very expensive bit of scrap that, according to some, is not currently recyclable.

Part of the very high cost of the EZA 130 is the very sophisticated and complex piece of electronics that :

1. Prevents the battery being run flat,

2. Prevents more than 100amps being drawn for any length of time

3. Contains an optimised 'big amps' charger.

 

If the electronics go wrong or the batteries run flat just once, the battery bank can be ruined. That can be £2,000 down the drain.

When you can get similar performance from 3 Top quality wet batteries, you need to have a really, really serious limitation on space and weight to go through the pain of installation, integration and maintenance.

 

 

I would suggest that they are considered only when integrated by the Motorhome manufacturer at build time, probably within 5 years?

 

 

One last point to watch out for : the battery in the link is a 100Ah battery, so supplies only 100Ah, but the publicity adds :

"(equivalent to 172ah in lead acid)".

 

Which is the most misleading garbage I have ever seen!!

It doesn't deliver 72Ah more than a wet battery, this LiFePO4 battery is only 100AH, but weight for weight it is lighter than a Lead Acid battery. So for the same weight/space as a lead acid 23kg battery, you could accommodate a second 72Ah battery. Not quite the same as delivering 172Ah versus 100Ah?

 

 

 

 

 

 

 

[veletron]

The 172AH claim comes from the fact (I believe) that to get a decent cycle life out of FLA, they should not be taken below 50% DOD, while the LiFePO4 gets a decent cycle life (a reported 3000 cycles) at 80% DOD

 

Therefore the 100AH lead acid is really 50AH and the 100AH LiFePO4 is really 80AH.

 

They are trying to give a lead-acid equivalent usable capacity (that most folks will understand). They have gotten it wrong of course, the 100AH LifePO4 is equivalent to about 160AH of lead-acid capacity.

 

Unfortunately, trying to explain to the man on the street that their 100AH lead acid is actually only 50AH, but that the 100AH LiFePO4 is actually only 80AH is a tough one, its far easier for marketeers to simply state a lead-acid comparable capacity.

 

As for the management, all of these newfangled LiFePO4 batteries have battery management built in. They are not simply individual LiFePO4 cells in parallel/series wired direct to the battery terminals! In fact on AliExpress you can buy individually the management boards that are used in the LiFePO4 I linked to.

 

The battery management charges parallel 'strings' of cells 4x3.2V in order to get 12.8V per string. These strings are individually monitored by the control board for voltage, temperature and current. It should not be possible to destroy the battery using a high-end motorhome charger since the management electronics will cut it off. But I'll agree that it wont then be able to charge the now disconnected battery! The electronics on the board also monitor the cell temperature, current, voltage in discharge mode.

 

LiFePO4 cells should not be allowed to fall below 2.8V and are fully charged when they reach 3.65V with 4 cells we then have 11.2V through 14.6V. The optimum voltage is 14.4V rising to 14.6V for the final 10%. Obviously a dumb charger is not going the handle the charging requirements, and will likely drop down to 13.8V float charge before the LiFePO4 is actually full. LiFePO4 cells will take a maximum of 4.2V per cell = 16.8V for a 12V system without sustaining damage or reducing their cycle life - provided the cell temperatures are properly monitored by the electronics. The lead-acid charger also wont raise the voltage for the final 10% so expect that last 10% to take eons.

 

So - for the majority of motorhome charging systems, these can indeed be simply 'dropped-in' but don't expect the battery to attain 100% SOC from lead-acid mains charger or alternator charger. Where an advanced battery charging scheme is in place in the motorhome eg the Sargent, or even a B2B it is likely that the electronics within the LiFePO4 will disconnect the cells from the supply before any damage occurs to the battery.

 

The EZA units are much more advanced (and 3x the price), they contain electronics to fully manage the charge/discharge process, including a true LiFePO4 charger with 2 stage charging and a LiFePO4 specific float voltage/threashold. They take whatever voltage they are fed from the vehicle electrical system (engine running), and turning it into the voltage they need. They also have a mains charger built-in, and an MPPT solar regulator built in.

 

Nigel

[veletron]

Forgot the link to the Chinese LiFePO4 in my original post: https://www.aliexpress.com/item/lifepo4-lifepo4-12V-100AH-polymer-battery-pack-for-Electrical-Vehicle-Solar-Wind-system-Electric-Bicycle-Battery/32702182571.html

[Tracker]

It's a very interesting discussion, but surely what most of us seek is simply the most economical and dependable means of providing 12 volt power when we need it?

 

Experience suggests that any new ideas, however laudible in theory, tend to be somewhat less effective in reality with much lost between the often misleading marketing hype and the practicalities of actual use?

 

Modern vans, like life, are needlessly complicated and what is really needed is simplification not more complication.

 

With simplification comes reliability and reliabilityy is, to me at least, far more important than squeezing every last theoretical drop out of a complicated system.

 

Rant over!!

 

 

 

 

[veletron]

EV's will drive this technology, reliability will get better and prices will come down. As a confirmed wild-camper, I don't consider lead-acid to be in any way elegant or reliable, or dependable. Crude, Cheep and cheerful is what lead-acid is to me. Just as phones are no longer powered by NiCad or NiMh batteries these days, Motorhomes of the future will not be powered by lead-acid.

 

Nigel

[Guest pelmetman]

If it ain't broke don't fix it ........is my mantra ;-) .........

 

I seem to recall the efoy was supposed to be the new nirvana a few years back......never met anyone who's got one to see if its really is the bee's knees :-S .....

 

Considering we're on our 4th leisure battery in 25 years I doubt the sums will add up for our usage :-| .......

 

 

[veletron]

pelmetman - 2016-09-16 2:41 PM

 

If it ain't broke don't fix it ........is my mantra ;-) .........

 

I seem to recall the efoy was supposed to be the new nirvana a few years back......never met anyone who's got one to see if its really is the bee's knees :-S .....

 

Considering we're on our 4th leisure battery in 25 years I doubt the sums will add up for our usage :-| .......

 

 

Agreed although to have achieved that, your demand must be very very low - eg limited time off hookup, or limited use? When lead-acid does finally die (and it will within the next 10-15 years), its likely that those with low demand would find a 50AH newfangled battery to be sufficient and to provide a longer service life than the equivalent set of FLA's. Getting back a bit of payload will be no bad thing either.

 

Nigel

[aandncaravan]

I don't have any doubts that there will be many new battery technologies in the future. However, people have been forecasting the end of the Lead Acid battery for about 30 years, yet it just goes on evolving.

 

The Relion website quotes just 1000 cycles at 90% DOD and only 2000 cycles at 80% DOD for the battery in your link? The much higher cycle life you quote is for much lower DOD levels?? http://cdn2.hubspot.net/hubfs/441554/docs/RELiON_SpecSheet_Final.pdf?t=1453755522909

 

Victron claim 4500 cycles for their Long Life Gel, with 1500 cycles still available at 80% DOD.

That is a much narrower gap than the Alpha batteries example,

So I don't see how your comparison works?

Especially so as Lithium (all technology) batteries have so far failed to live up to the hype. Just ask anyone who has had a Lithium powered Drill, etc.

 

ALL batteries currently available have the longest life when only shallow discharged. Deep discharges shorten the life of all batteries.

Ask Tesla Car owners if they get the cycle life promised. It is not the same Lithium technology, but like all Lithium technology before they were promised the Earth, but didn't get it. No reason to believe that LiFePO4 will deliver what the Sales teams say.

 

 

Some of the Lithium Batteries might have overcharge and discharge electronics built in, but that may mean they will shut down and not allow any charge.

It also assumes the electronics won't go wrong. This isn't just a £70 battery that will be scrap if things don't go to plan, it is a potential £2,000 battery pack that is destroyed if either the charger isn't suitable or the battery electronics fail.

That is quite a risk!!

Accidentally drop to 95% DOD and the battery will deliver a max of just 500 cycles.

 

 

Many British built Motorhomes up to 2007 had a 13.5v charger which won't get a Lithium battery even half charged let alone the 90% often suggested. So the sales hype that 'any charger will do' shows, again, that the Motorhome market isn't understood by those targeting it.

How will that 'continual discharged state' affect a Lithiums life?

 

But even that aside, 'dropping in a Lithium pack' into a current Motorhome won't achieve the lithium battery potential of charging 3 times faster if the charger has only got 16amps.

To reach the potential of a big Lithium pack you might be looking at 60+ amps.

 

 

If you read the good sites they all recommend nothing but a dedicated LiFePO4 charger for safety, long life and to reduce risk.

 

 

Compare the Victron £190 battery against a Lithium battery and the cost and very significant risks don't make sense to me?

 

When a 'conventional' Victron Energy battery is not that far off a Lithium (even the LiFePO4 'optimistic' claims) for a whole lot less money and almost zero risk I know what I would recommend to a customer.

 

 

[Guest pelmetman]

veletron - 2016-09-16 7:44 PM

 

pelmetman - 2016-09-16 2:41 PM

 

If it ain't broke don't fix it ........is my mantra ;-) .........

 

I seem to recall the efoy was supposed to be the new nirvana a few years back......never met anyone who's got one to see if its really is the bee's knees :-S .....

 

Considering we're on our 4th leisure battery in 25 years I doubt the sums will add up for our usage :-| .......

 

 

Agreed although to have achieved that, your demand must be very very low - eg limited time off hookup, or limited use? When lead-acid does finally die (and it will within the next 10-15 years), its likely that those with low demand would find a 50AH newfangled battery to be sufficient and to provide a longer service life than the equivalent set of FLA's. Getting back a bit of payload will be no bad thing either.

 

Nigel

 

Our leisure battery will usually last 3 days before we need to go for a run or find hookup, which is about the same as our water and cassette capacity........

 

Which has worked fine for us, as we rarely stay on an aire or wild camp for more than 2 nights ;-) .....

 

 

[veletron]

Its £1000, not £2000 still way out of my price league!

 

Imagine if phones still had NiCad batteries - lifetime today would be roughly one hour. I can see these taking off, not for everyone, but for folks with a high demand.

 

I've not yet had a lead-acid battery live up to either the specs on the side or my expectations - so I'm used to technology not meeting expectations. Not sure where you got your DOD vs Lifecycle figures from, the graph is pretty clear. 2000+cycles at 100% DOD, 4000 at 80% DOD, 6000+ at 50% DOD.

 

 

 

[colin]

I have next to me in the van right at this moment a Li-ion battery with roughly the equivalent storage as a 40ah lead-acid, I can pick it up between thumb and forefinger, just looked online and it seems the replacement cost is about 135 dollars, so probably about the same in £. Just needs a company to produce a 12v version with greater capacity in quantity and the price will tumble.

[aandncaravan]

Yes I did see that chart. However, as every good Lithium Iron information source says the batteries will be destroyed if discharged to 100% (95% being the general recommended minimum) I took the '100% discharge' as a sign that their entire information was suspect.

 

I did pick up on the fact that the Lithium battery became equivalent to an 80Ah battery, losing 20Ah, after a while though.

Which I have to applaud it being published, many Lead based battery manufacturers quote the figures for a new battery and forget to mention how the picture deteriorates, in some cases dramatically, after 12 months.

 

 

 

[Muswell]

aandncaravan - 2016-09-17 11:00 PM

 

Yes I did see that chart. However, as every good Lithium Iron information source says the batteries will be destroyed if discharged to 100% (95% being the general recommended minimum) I took the '100% discharge' as a sign that their entire information was suspect.

 

 

 

 

I too find that as soon as I discover fundamentally wrong in an article or advertising I suspect that everything was written by someone who didn't understand the subject.

[veletron]

Noticed from links posted on another thread about battery charging that Votronic have a 45A LiFePO4 on-the-go B2B charger: http://www.votronic.de/index.php/en/products2/series-vcc/lithium-version/vcc-1212-45-lithium

 

Nigel

[Alanb]

Nigel,

 

I think that you may find the following link interesting. http://www.manins.net.au/motorhome/12V_electrics.html#lithium_battery

 

I came across this site some time ago when I was about to replace my own batteries. I managed to find all of the suppliers linked from the website, but I did not think that shipping a pre-assembled battery from Australia would be economic. Individual cells were available from the EU, but I eventually decided that the time required for the project, which would have to include making up the battery, might evoke matrimonial disharmony. I therefore followed the FLA / B2B route, using a CTEK D250S DUAL, grafted around the existing CBE PC200 system.

 

Alan

 

 

[Colin Leake]

Batteries related to those used in latest Samsung mobile phones and in the Dream Liner aeroplane! Puts me off a bit! An early use was in electric model racing cars and motorbikes. Thanks to special chargers and speed controllers their use in now quite safe. In the early days it was not uncommon for them to catch fire. Even now they are still enclosed in soft cases so that if the worst happens they catch fire rather than explode!

[colin]

Colin Leake - 2016-09-26 7:37 PM

 

Batteries related to those used in latest Samsung mobile phones and in the Dream Liner aeroplane! Puts me off a bit! An early use was in electric model racing cars and motorbikes. Thanks to special chargers and speed controllers their use in now quite safe. In the early days it was not uncommon for them to catch fire. Even now they are still enclosed in soft cases so that if the worst happens they catch fire rather than explode!

 

A few on here like us have electric bikes, just done a quick rethink on capacity and my bike battery has around same usable capacity as a 50ah lead acid and I just tried lifting it on my little finger, try that with a lead acid. And remember lead acid produce explosive gas when charging, will produce toxic fumes, and if split will spill acid everywhere. Someone I know did have a li-po battery on his NV rifle sight explode and nearly blind him, but on otherhand many years ago a friend got badly burnt when a lead acid he was trying to charge exploded.

[aandncaravan]

veletron - 2016-09-26 12:01 PM

 

Noticed from links posted on another thread about battery charging that Votronic have a 45A LiFePO4 on-the-go B2B charger: http://www.votronic.de/index.php/en/products2/series-vcc/lithium-version/vcc-1212-45-lithium

 

Nigel

 

 

The Votronic is a very good B2B charger, the Gel/AGM/Wet version of which is part of our range of B2B units that work in harmony with the existing Power Distribution/Charger, not against them, see : http://www.aandncaravanservices.co.uk/battery-to-battery-chargers.php

.

 

The Votronic is one of our range of three units starting at £99 that boost the Alternator voltage to the Habitation battery to the optimum, so improving Alternator effectiveness, without the high battery dehydration voltages of the old Sterling B2B's.

 

Unlike the Sterling units which are generally connected Battery to battery, our units link in directly to the Elektroblock so functionality is unchanged.

 

One good side effect of these units, can be a more efficient Fridge/Freezer, as the Voltage drop often associated with the large power draw of the Fridge is counteracted by the B2B.

 

We have been installing the entry level B2B in Caravans since 2013. Some Caravans have a very long cable run from the Alternator at the front of the Tow vehicle to the rear of the Caravan of many metres, often with inadequate sized cable to prevent the voltage drop that occurs

 

A B2B installed in the Caravan close to the Power Distribution unit brings the voltage up to the optimum level without cooking the habitation battery.

 

 

It is also proving a good solution to the alternator 'shutdown' that can occur in a Tow car with Brake Energy recuperation. Did the first on Saturday specifically to address the Fridge going into 'error' with a late model Tow car.

The B2B ensures the Fridge and Habitation battery always get 14.4v regardless of the Alternator state.

Thanks to a 'Heads Up' from KevinA we have added the Votronic units to the B2B fitment range.