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Discussion Starter #21
I am not using the Ctek yet. Using the Victron Energy Cyrix Li-Ct.
This is being used by many to charge lithium batteries.
I would think there is a connection problem somewhere.
Will check for resistance tomorrow.


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Discussion Starter #22
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".
Finally the system is running. I had not wired up the trigger wire to the Cyrix. I did not use this wire in the old Cyrix Ct. The battery is charging at 21A. I started driving with the battery with the aircon and dashcam on at 75% and when I returned after 25 minutes, it had risen to 79%.
A lead acid battery will not give that sort of charge. My starter batter of 100A was at 83% when I left and it was at 84 when I arrived home.
I will monitor this over the next few days.
 

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Aircon, Dashcam, full headlights, ANYTHING you can turn on will NOT take enough current from the alternator to reduce the charging current to a leisure battery!!! (Via a PROPER split charge system!)
You have at least a 120 amp alternator....maybe the 150 on your van.....that should leave at least 50 amps spare after the 1st 5 mins of driving!
You have a "toy" 25 amp charger for it....get a 50 amp one and stop worrying.

ALL these "percentage" numbers are just a "guess" anyway.......
 

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Discussion Starter #24
ALL these "percentage" numbers are just a "guess" anyway.......
Guessing? I am using the Ctek Battery Sense.
I am in no hurry to get the battery to full charge in an hour when I need the full about 2 or 3 times a year.
For use otherwise I will manage with 50% with a wide margin.
Do you need a V8 engine to drive to the shop down the road?


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Guys you are doing this the hard way check posts about battery under my monicure about 3 yrs ago. Winstons still charges to 13.2-13.3 volts as of today same as new. Now days you can get single package batteries similar to the image above that are cranking like mine. 4 cells means when one dies you could replace a cell and price about Au$1.80 x amphrs x volts... have a balancer and monitor but no BMS (BMS means you can't crank) checked temps over summer up a 100km step road oil hit 118 deg battery hit 65deg. 80deg is max temp can fit a cooler fan under cells if your worried.

If I was doing it again I'd look at 90 or 100 amps which are taller set them sideways. reason is they have a smaller foot print than my 130amps.. which is a tiny bit too big a foot print

never bothered with solar as bat runs lights (multivan) small fan, Engel 40 litre and radio for 4-5 days might get down to 12.8 volts and will easily start the car. Only once had it worry me when -2deg (read about cold lithiums) but let it sit a minute and tried again start just fine. Bat monitor max 14.2 volts settles back to 13.3volts after an hour. As I use standard wiring Consumables turns off the system at low volts guessing that will be 12 volts don't know the figure never happened.. Bat empty is 10.5 volts.
 

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Discussion Starter #26
I looked at the Winston cells but I live in Norway. Building a battery with 4 cells will work out mor than buying a battery like I did.
Met a German guy last year running Winstons and he did not use a BMS.
I worked out that the Winston cells came up the same price as the Victron Energy battery after paying the VAT and taxes. That should be about 1300 euros.
The problem here is not heat but the cold in the winter. We need a heating element to temper the batteries.



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If you search on the net, Victron use the Winston cells in their 90 amphr or used to... if you operating below 0deg I understand you may need a heater...
 

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"Guessing? I am using the Ctek Battery Sense. "

Yeah....and what does that do?
It "makes an estimate" of the battery capacity from the charge voltage!
Does it "know" how many A/H it has in it...NO
Does it do a "discharge under load" test....NO..
Can it measure the state of the chemicals in the battery....NO

It's a "guess" that is computed by the voltage only!

I had a battery with a duff cell....it would happily go to 14.4 volts on charge....but one cell was "dead".
Your "Battery Sense" would show it at 100%......but take it OFF charge and it dropped to 11.4 volts!
 

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Discussion Starter #29 (Edited)
"Guessing? I am using the Ctek Battery Sense. "

Yeah....and what does that do?
It "makes an estimate" of the battery capacity from the charge voltage!
Does it "know" how many A/H it has in it...NO
Does it do a "discharge under load" test....NO..
Can it measure the state of the chemicals in the battery....NO

It's a "guess" that is computed by the voltage only!

I had a battery with a duff cell....it would happily go to 14.4 volts on charge....but one cell was "dead".
Your "Battery Sense" would show it at 100%......but take it OFF charge and it dropped to 11.4 volts!
No it does not make an estimate. When it reaches a percentage, it stay there, even overnight. I suggest you get one of these so you wont have to guess.
You are the one who is guessing since you have never used it. It is configured for 100A. Here too you are guessing that it cannot be done.
Show me a battery that will show a full 14.4V with a dead cell. This has happened to me with a 2 year old battery. The app showed a discharged battery. Since this was a warranty case I took it to the shop and they measured one cell at about 1V and the total voltage of the battery was 11,5V. I had to push start the car to get there. When I got there, the battery was showing as discharged in the app, red.
When I got there and turned off the engine, it would not crank again.
See, you are guessing again.
With this I can monitor the state of charge of the battery and recharge when needed without pulling out a voltmeter.
 

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So......your "App" is inside the battery, measuring the specific gravity of each individual cell is it?

My starter battery was quite happy to show 14.4 volts on charge on both the Scangauge and my DEFA display.....but left to stabilise , it was at 11.6 volts......ONE dead cell, so the other 5 were being overcharged.

Still...never had to "push start" my automatic van....it still cranked over and started. :whistle:
There again....I never had to fork out a fortune for NOT making sure my timing belts were good....:eek:

Voltmeters are NOT a way to check the "quality" of charge in a battery anyway.
You need at least a 50 amp load across the terminals, and a 4 wire meter to measure how good it is......since "sealed" batteries can no longer be tested by the specific gravity method.
 

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Discussion Starter #31 (Edited)
So......your "App" is inside the battery, measuring the specific gravity of each individual cell is it?

My starter battery was quite happy to show 14.4 volts on charge on both the Scangauge and my DEFA display.....but left to stabilise , it was at 11.6 volts......ONE dead cell, so the other 5 were being overcharged.

Still...never had to "push start" my automatic van....it still cranked over and started. :whistle:
There again....I never had to fork out a fortune for NOT making sure my timing belts were good....:eek:

Voltmeters are NOT a way to check the "quality" of charge in a battery anyway.
You need at least a 50 amp load across the terminals, and a 4 wire meter to measure how good it is......since "sealed" batteries can no longer be tested by the specific gravity method.
There you are guessing again. My timing belt never snapped and I forked out some money when my tensioner roller disintegrated and took my fan belt along. I threw in a brand new tensioner and 3 rollers for good measure. This doubled or tripled my bill at the VW dealer. It might be a fortune for you but it never made a dent in my finances.
I don't need lessons in voltmeters and specific gravity. Yes I know perfectly well what surface charge is and load checking of a battery.
If you managed to start you car with a flat battery, this must be a world first. 12.7= full. 11.7= discharged.
 

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Finally the system is running. I had not wired up the trigger wire to the Cyrix. I did not use this wire in the old Cyrix Ct. The battery is charging at 21A. I started driving with the battery with the aircon and dashcam on at 75% and when I returned after 25 minutes, it had risen to 79%.
But don't you need a voltage controller for the right voltage? I've read that it's not recommended to charge lifepo4 without a dc-dc charger because lithium is very sensitive for voltage charging, not like lead batteries.
 

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Discussion Starter #33
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But don't you need a voltage controller for the right voltage? I've read that it's not recommended to charge lifepo4 without a dc-dc charger because lithium is very sensitive for voltage charging, not like lead batteries.
Not according to the shop. The Victron Li-Ct should regulate the charge but recomend a Dc-Dc charger for faster charging.
The Victron does not charge as fast but for my use I dont need to bring the battery to full charge just after I leave home.
Besides there is always charge in the battery and we are talking about filling up about 20% of the battery.
A Dc-Dc charger is safer for the alternator as it does not overheat the alternator.
The told me the alternator can self destruct if you run the alternator on max output for prolonged periods charging a lithium battery with a Victron VSR.
They have sold thousands of batteries and had only one customer who fried the alternator.
With my driving style, no worries.


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Not according to the shop. The Victron Li-Ct should regulate the charge but recomend a Dc-Dc charger for faster charging.
But it doesn't regulate voltage, because it's a power relay (with smart functions like switching on after some amount of seconds).
It's not about fast/slow charging, more about the wrong voltage of alternator (it's just not build to charge lithium). For lifepo4 you need 14.2V constantly, I doubt that it will be something like this from the alternator. And even if it will be constant 14.2V, then it will be very bad for the starter battery.
Of course, the battery can charge, but the life of the battery will be less than if it would be charged properly. And I guess it will also shorten the life of the alternator (but the cost of an alternator, or even the voltage regulator) is nothing compared to the lifepo4 battery.
 

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Discussion Starter #36
My car charges at 14.1-14.4V


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Vic, the alternator is voltage controlled, current regulated.
So, 14.2 to 14.4 volts is never a problem for the starter battery....the current it takes will fall off exponentially as ITS voltage rises.
A good 3 -5 stage mains charger will actually take the battery (lead acid) up to around 15.5 volts for a few mins, to remove the sulfur from the plates!
THAT is when you have to be careful, as it "supposed" to gas at that voltage.

13.8 volts (that they call "maintenance" charge, only keeps the battery at that level...it will NEVER recharge it if it has gone below 90%. (Again, talking about lead acid...)

As for alternators....they are designed to give a certain current, at a certain RPM....usually around 12 - 20 thousand RPM....that is why the pully is 4-5 times smaller than the driving pulley.....and a fan also rotates at that speed to cool it.

My boat, diesel engine, normal cruising RPM 1500 had a 10:1 ration on the pulley to a 120 amp alternator. (so alternator rotating at 15,000 RPM).
This was charging a 700 A/h battery bank....with occasional use from a 1500W invertor that took around 150 amps on "full wack".....engine DID slow down (and make a "heavy noise") when it was used to boil a kettle (1.3kw) or run the microwave (1kw).
Never had a problem with the alternator after 8 years of it doing this.....I even built a circuit that made IT charge at 15.5 volts for 5 mins/day.
 
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