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Discussion Starter #1 (Edited)
Finally I bought a LiFePo4 battery. It is rated at 96A and very low. It fits under the drivers seat with no problems.
I have also got a CTEK Dual 250SE which is a DC-DC charger. This has a MPPT solar regulator built in.
So far onlt the charger has arrived and the battery should be here next week.
The lithium weighs only 11,5 kg while my 120A batteries weigh 44 kg.
The lithium will give me double the usable power that I could get from the wet battery.
The battery has bluetooth and a heating foil that tempers the battery to plus degrees in winter.



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Finally I bought a LiFePo4 battery. It is rated at 96A and very low. It fits under the drivers seat with no problems.
I have also got a CTEK Dual 250SE which is a DC-DC charger. This has a MPPT solar regulator built in.
So far onlt the charger has arrived and the battery should be here next week.
The lithium weighs only 11,5 kg while my 120A batteries weigh 44 kg.
The lithium will give me double the usable power that I could get from the wet battery.
The battery has bluetooth and a heating foil that tempers the battery to plus degrees in winter.


Wow - they aint cheap :oops:
 

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Discussion Starter #3 (Edited)
Not cheap but I get the full 12,8V down to 90% discharge. With wet batteries you are at 12,2V at 50% and and discharged at 11,7V on 40%.
A lithium battery has double the usable power as compared to a wet battery.
A lithium battery can be charged up in as little as 60 minutes.
If you are off grid, you just need take a short drive to get it up to 75% charge.
I would say this is a better and cheaper investment than much of the blings like lowering springs, banded steel wheels and «devil look» Audi style headlights.


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Wow. I didnt know you could get these for leisure batteries. Presumably a 100w solar panel and one of these could keep you off grid for some time?
 

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Discussion Starter #5
With solar power I think you can be off grid until you run out of food and water.
I have spoken to people who have lithium and they say they dont need to monitor their batteries.
Just a short drive and their batteries are full.
One guy with solar power said he saves money because he does not have to pay for electricity on camping sites. He has never run out of juice.


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Batteriet er utviklet av Skanbatt i samarbeid med Shenzhen TopBand Batteri CO, LTD.
Thanks, then probably it can be possible to find it even cheaper under another name.
A lithium battery can be charged up in as little as 60 minutes.
If you are off grid, you just need take a short drive to get it up to 75% charge.
That charger shows it can charge up to 25A, how will it charge 100Ah battery up to 75% for 60 min?
 

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Simple physics....
No matter what charger you use, you can't get more amps out of the alternator than it will provide!
On tickover, that is about 10% of it's rating.
So, if you have the biggest (150A) alternator fitted, on tickover expect around 15 amps......just about enough to "cover the running costs" of the van.
At 2000 rpm, you will get around 75% alternator output....so just over 110 amps.

Alternators do not give full power until rotating at around 10 - 12,000 rpm (look at the difference in pulley sizes, and notice there is often a 3.5:1 ratio to the alternator.)
So...need to be using at least 3000rpm at the engine to get full output from the alternator.

Indian is pulling numbers out of the air....NOT possible according to the laws of physics/electrical theory.

Yeah, Tesla can charge batteries that fast....with a 100kW charger.... BUT, with the biggest T4 alternator, you have 2.16kW....LOL

As you point out...that "toy" charger will give 25 amps.....that means at least 4 hours to charge the battery..assuming 100% efficiency!

That's from a FLAT battery....but even if only at 50%...it's still 2 hours....
 

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Discussion Starter #10
Thanks, then probably it can be possible to find it even cheaper under another name.

That charger shows it can charge up to 25A, how will it charge 100Ah battery up to 75% for 60 min?
Not with the CTEK Dual 250SE. If you use a Victron LI-CT VSR it will dump the alternator output into the lithium battery.
I bought the CTEK to be able to use solar power next year.
Until then I will be using the Victron.
With my use I can manage very well with the 25A from the CTEK.


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Discussion Starter #11
Simple physics....
No matter what charger you use, you can't get more amps out of the alternator than it will provide!
On tickover, that is about 10% of it's rating.
So, if you have the biggest (150A) alternator fitted, on tickover expect around 15 amps......just about enough to "cover the running costs" of the van.
At 2000 rpm, you will get around 75% alternator output....so just over 110 amps.

Alternators do not give full power until rotating at around 10 - 12,000 rpm (look at the difference in pulley sizes, and notice there is often a 3.5:1 ratio to the alternator.)
So...need to be using at least 3000rpm at the engine to get full output from the alternator.

Indian is pulling numbers out of the air....NOT possible according to the laws of physics/electrical theory.

Yeah, Tesla can charge batteries that fast....with a 100kW charger.... BUT, with the biggest T4 alternator, you have 2.16kW....LOL
I am not pulling numbers out of the air. I have been talking to loads og people with campers and boats who use lithium. I am just telling what they told me. They all say the same.
They have never run out of power.
Couple sailing in the West Indies told me that they have never run out of power since the switched to 3X100A batteries.
It was a different case with their AGM batteries.


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Not with the CTEK Dual 250SE. If you use a Victron LI-CT VSR it will dump the alternator output into the lithium battery.
Got it, just find out that LiFePo4 can be charged with much more Amps than wet batteries: 50A recommended, 80A max for 100Ah battery. Sounds really good.
 

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Discussion Starter #13
Thanks, then probably it can be possible to find it even cheaper under another name.
If you can do without the bluetooth and the heating foil they cost about £450 for a basic 100A battery in Norway. In the winter you will have to turn off the charging with a switch until the battery is above zero.
With 3000 charge cycles and the extra power, they turn out cheaper than the wet batteries. LiFePo4 batteries don't have the memory effect.

www.provolt.no
 

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Yeah....but that crappy 25amp charger you have will NEVER give you that performance......
50 amp "recommended".....and you bought a 25 amp version?!?!?!
 

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Discussion Starter #15 (Edited)
Yeah....but that crappy 25amp charger you have will NEVER give you that performance......
50 amp "recommended".....and you bought a 25 amp version?!?!?!
This «crappy» charger is used by many to charge a bank og up to 4 batteries. With a wet battery I need to charge fast because the usable power is half the rated capacity.
With lithium you get the full power all the way to 90% of the battery.
Another thing is that you will need this crappy charger if you have one of those smart alternators fitted to Euro 5 and 6 cars today, stepping up the voltage from below 12 to 14,8V
The shop told me to just connect the battery and forget about it.
With this battery I wont need to turn off the fridge and camera when I park.
My alternator is rated 120A but I measured at the battery earth at 67A.
I did this at night just after I replaced the regulator and I will check this out in daytime.


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Discussion Starter #16
I installed the battery and the Cyrix VSR. I measured only 18A charge at the lithium battery.




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Discussion Starter #18
What are you measuring it with?
Clamp ampere meter. Battery was at 77% and drove 50 km and it was at 77% at the end of the drive. The wet battery would have gone up by 3% on this drive.
I drove to Sweden and Lillehammer with the wet battery at 70% and it was at 100 when I arrived. Total kilometers was 500.
 

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Discussion Starter #19
Something is wrong. The lithium battery does not charge. I measured 55A at the starter battery positive to the VSR before the fuse but only 18A after the fuse. From the VSR to the lithium battery I measure 18A.
The app says standby while driving but discharging with dashcam connected.


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The specifications for that battery state up to 60 amp charge current....
Anbefalt lademetode: <60A til 14,4V, deretter 14,4V til 0,02C (2A) (CC/CV)
Anbefalt ladestrøm: <60A
Maks ladestrøm: 100A
Maks ladespenning hvor BMS bryter: 15,2V +-0,2V

Even I understand that much Norwegian. o_O

That 25A CTEC is just not gonna "cut it".
 
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