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RussnSue

Report on two years of Lithium battery operation.

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As promised, here is the second annual report on the LiFePO4 batteries in our van.

Over the last 12 months our batteries enjoyed life on 240V charger for just less than 6 months and the remainder on solar charge. The chargers are both configured to boost the batteries to 14.4 Volts, then float them at 13.8V (240V charger) or 13.7V (solar). We have 360 AH of capacity of which just less than 290 AH is available from the fully charged state. Typically, our state of charge in the morning (before solar charging commences) is between 70% and 80%, so they aren't working very hard. The lowest the battery was ever discharged to was a SOC of 50%.

Determining the life expectancy of LiFePO4 batteries is quite difficult. I have to get technical here. From fully charged, LiFePO4 batteries deliver their power at 13.4 Volts for a short while, then 13.3 Volts for a little longer and then settle at 13.2 Volts, where they will stay until they are discharged by 80%. After this, if you continued to discharge the batteries (apart from ruining them) you would see the voltage drop away pretty quickly. If the life expectancy of the batteries were to be reduced, the capacity would be diminished and therefore the time to reach 13.1 Volts would be less. My solar charger records the maximum and minimum voltage of the batteries each day. As yet my batteries have never dropped to 13.1 Volts, so I conclude that I must still have plenty of capacity, based on the fact that when the SOC was 50% the voltage was still 13.2 Volts.

I am going to have to learn to "trust" the batteries more. That is, allow them to discharge lower (because they can) rather than what I am doing now - which is, essentially, treating them as though they were AGM batteries and tailoring my power usage to no more than 35% of capacity. By forcing myself to do this I might get to watch a bit more telly or run the computers for longer.

Physically there is nothing to see that would indicate any issues with the batteries.

Conclusions: The weight saving is definitely worth it. The extra expense seems to be worth it, especially when I read, on this forum, about people being on their second and third set of AGMs since buying their van. The batteries need zero maintenance. So far so good.

Cheers

Russ.

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Hi Russ,

32 Kev again, the report on the LiFePO4 batteries sounds promising, I hope there will be a 12 month follow up again.

A question for you, I fitted the Sterling Power 60amp charger to my van and all is working well, could you tell me did you bridge the two unused charging poll's to the one used that runs to the battery positive.

The reason I ask is in the user manual it states that if only one of the three charging terminal is used then the other 2 terminals should be bridged to the one working, then further on it states that this is not necessary with the new technology but good practice to do so.

Cheers

32KEV

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Hi Russ,

32 Kev again, the report on the LiFePO4 batteries sounds promising, I hope there will be a 12 month follow up again.

A question for you, I fitted the Sterling Power 60amp charger to my van and all is working well, could you tell me did you bridge the two unused charging poll's to the one used that runs to the battery positive.

The reason I ask is in the user manual it states that if only one of the three charging terminal is used then the other 2 terminals should be bridged to the one working, then further on it states that this is not necessary with the new technology but good practice to do so.

Cheers

32KEV

Hi Kev

No mate, I didn't bother to bridge the terminals. The unit is working fine. If I take the cover off for any reason I may do it, but otherwise.....

Cheers

Russ

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Hi Kev,

I have the 60amp Stirling Charger and 360ah of lithium batteries installed in our van. I did bridge the 2 outlets, though I do not know if it makes a difference. As a matter of intetest, I used the "custom" charge settings as it suited my batteries better that the generic lithium setting.

Regards

Chris

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G'day Russ



Thanks for the 2 year update. Very interesting.



We're looking to get a new van this year with Lithium despite Kedron still being reluctant to fit them.



Do you know if the LiFePO4 is still the ants pants in Lithium options, or is there a more optimised option available now?



Cheers


Alan


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G'day Russ

Thanks for the 2 year update. Very interesting.

We're looking to get a new van this year with Lithium despite Kedron still being reluctant to fit them.

Do you know if the LiFePO4 is still the ants pants in Lithium options, or is there a more optimised option available now?

Cheers

Alan

Alan,

FYI , Kedron now offer a lithium option which is supplied by Enerdrive.

cheers Greg

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Greg, that is really useful information re the factory now having a relationship with an installer of Lithium. Are you able to provide more detail? If so, it might be an idea to start a new thread on the topic.

I know the factory doesn't re-open until 19 January so they won't be available for comment before then.

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Hi Russ,

From memory, you have 4 x 90a/hr Winston batteries in your van.

I am currently looking at them and was wondering your thoughts on 2 x 200 a/hr battery cells (8 cells in total) compared to the 4 batteries.

I'm not sure if it applies to lithium but I was once told that bigger was better in agm batteries.

I would appreciate your thoughts.

Cheers,

Ian

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Hi Ian



Sorry about the delay in responding. Thanks to Telstra, the ADSL service at Evans Head has been off for the last three days.



To answer your question, capacity is capacity. 400 Amp Hours rated capacity will equate to 320 AH of usable capacity, which is a pretty handy amount to have. If it is cost effective to go down this road, then I would. If it is cheaper to go with 4 x 100 AH batteries, then do that. You will end up with the same amount of usable capacity whichever way you go. Just go with a reputable brand and you'll have no problems.



Cheers



Russ


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Hi Russnsue, Chris and Lynn,

A question relating to the Sterling Power 60 amp Charger.

As I said earlier I fitted this charger to my van because it had the generic Lithium charge on it.

As my AGM are now over two years old, (this is my third set) and I getting worried that I will have to replace them shortly, so time for me to gather more information.

 

Can the Sterling charger charge lithium batteries as is, or do you have to have other bits and pieces of electrical equipment.

 

If you fellas could help me out with what I have to do, and what I need to purchase to change to Lithium when the time comes, I wont be spending weeks, or months trying to gather the information and bits and pieces needed to change over.

 Hey Russ, I may have missed it but have you had an update on the lithium batteries since the 2 years, and Chris how are your lithium batteries going, still pleased with them I hope.

 

Looking forward to your replies.

 

32 Kev

 

 

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Hi 32 Kev,

You should be getting 5 years or more from your batteries . With AGM you need to keep them above 12.2 volts . When they get down to 12.2 volts you have used 50% of there power . AGM are designed to work down to 12.2 volts and then recharge to about 13.8 volts .

 

Cheers Nev

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Hi Nev,

 

Thanks for the advise, in brief I will fill you in on my battery failings.

 

My ATV is just over 8 years old, we live in our van and our batteries survive 10 months of the year on solar and generator, we run compressor caravan fridge, 76 litre national luna freezer, a 40 litre Engel freezer, and a 32 litre Engle fridge on the very rare occasion have the 4x120ah AGM caravan batteries fallen below 12.3V. I also have 2x 120AH AGM batteries in the vehicle, and they link up to the van at night.

Our first set of Ritar batteries lasted 34 months, our second set of Ritar batteries lasted 36 months, this latest set (not Ritar) are at 29 months, and at the moment still OK.

 

So you can see why I am a little concerned about this last set of batteries, I am not a wiz on batteries but I am led to believe that a battery has so many cycles it can do before it will fail, mine in 12 months do a minimum of 300 cycles, so I guess about 2.5 years is not to bad.

 

Keeping fingers X

 

Cheers

 

32 Kev

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Hi 32 Kev ,

We also live in our van and have 4 x 120ah batteries and 660 watts of soar . Yes they do have so many cycles , the less you drain everyday the longer they last .

 

Cheers Nev

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