Help please - lithium, solar etc

[TJG]

My T6.1 is on its way to Oz and it will have a full camper conversion. I’ve bitten the bullet and have opted for a 300W solar panel on the pop top, a 100Ah Lithium battery and a Victron 100/20 MPPT controller/ dc dc charger (I think it charges!).
Anyway, I’m pretty ignorant re how all this works so please correct me if I’m wrong.
When driving the alternator initially recharges the starter battery then, once full switches to the Victron which starts charging the lithium battery. Meanwhile the solar panel up top is also busily feeding power into the Victron (assuming sunshine!)
When parked the solar continues to feed the Victron. However, it’s 37C here today so I park in the shade and deploy my 180W solar blanket and plug it into my external Anderson plug. The blanket continues to put power into the Victron. As the shade moves my 300W panel is in the sun again & the blanket is still deployed.
Can the Victron handle all this? Have I got the process wrong?
Please help!!!

 

[AussieMick]

The theory of parking in the shade and using the portable panel is correct or your van will be really hot.
When I am in hot weather my fridge runs a lot more often drawing more power from your leisure battery so the more solar panels the better.
We did a 5 week trip up to Alice Springs and surrounding ranges in September and every day was 35c or more so my fridge seemed to be running nearly all the time.
I had 150w panel on my roof and a portable 150w blanket. My battery was a 120w AGM.
When I got home I changed to a 150w lithium lifepo4 battery and got another 200w portable blanket.
So you have a fair bit of solar panels too which you will be glad of in summer. Once I got back to Adelaide because the temperature was much lower my fridge hardly cycled and my roof panel was enough to keep battery charged.
It appears your Dcdc charger will handle 20amps.lf your panels output more than 20amps it will only use 20amps to your battery.
But even when I have 350w of panels in full sun I rarely go over 20amps output.
The good thing with lithium lifepo4 is you can draw them down to about 10 to 20percent where as an agm should only be used down to 50 percent or you shorten your battery life.
Sorry for the long winded post but I hope it helps.

 

[Petro]

Im assuming you mean the The Victron SmartSolar MPPT 100/20, which is for converting power from you solar panels to the battery, but as far as I know that unit is not for battery-to-battery charging. For that you will need a dedicated unit, one example is Victron Orion-Tr. This will be connected between the 2 batteries.
The MPPT will be connected between your lithium battery and the panels, and if both of those panels are 24V architecture then the MPPT can handle it. It handles up to 580W when panels are 24V architecture and 290W when in 12V.

 

[TJG]

The theory of parking in the shade and using the portable panel is correct or your van will be really hot.
When I am in hot weather my fridge runs a lot more often drawing more power from your leisure battery so the more solar panels the better.
We did a 5 week trip up to Alice Springs and surrounding ranges in September and every day was 35c or more so my fridge seemed to be running nearly all the time.
I had 150w panel on my roof and a portable 150w blanket. My battery was a 120w AGM.
When I got home I changed to a 150w lithium lifepo4 battery and got another 200w portable blanket.
So you have a fair bit of solar panels too which you will be glad of in summer. Once I got back to Adelaide because the temperature was much lower my fridge hardly cycled and my roof panel was enough to keep battery charged.
It appears your Dcdc charger will handle 20amps.lf your panels output more than 20amps it will only use 20amps to your battery.
But even when I have 350w of panels in full sun I rarely go over 20amps output.
The good thing with lithium lifepo4 is you can draw them down to about 10 to 20percent where as an agm should only be used down to 50 percent or you shorten your battery life.
Sorry for the long winded post but I hope it helps.

Thanks for your long winded reply!! Very reassuring

 

[TJG]

Im assuming you mean the The Victron SmartSolar MPPT 100/20, which is for converting power from you solar panels to the battery, but as far as I know that unit is not for battery-to-battery charging. For that you will need a dedicated unit, one example is Victron Orion-Tr. This will be connected between the 2 batteries.
The MPPT will be connected between your lithium battery and the panels, and if both of those panels are 24V architecture then the MPPT can handle it. It handles up to 580W when panels are 24V architecture and 290W when in 12V.

Think the panel is 12V. Will need to check re charger