what is the best way to use a 24v Lithium battery with a Vmp=30-31v Solar Panel

[akumd]

Hi, I have a single Panel with below specs,
Pmax=550W Vmp=31.6v Imp=17.4A Voc=37.9v Isc=18.52A
Used for about 1 year now.(with a 12v Gel battery. Planning on switching to a Lithium battery as Gel battery capacity has dropped)
I tried to find another panel with same specs but could not find any in my country.
Therefore making 2 panels series is impossible.
What would be the most efficient way to use this panel with a Lithium battery ?
1. Use a 12v LifePo4(3.2x4) battery with a MPPT controller (+12v inverter) ?
OR
2. Use a 24v LifePo4(3.2x8)/Lion(3.7x7) battery with a PWM controller (+ 24v inverter) ? (saw few videos stating that PWMs are bad for Lithium batteries)
OR
3. Use a 24v LifePo4(3.2x8)/Lion(3.7x7) battery with a MPPT controller(is this even possible ? seems most MPPT controllers need PV voltage to be 1.5/2 times the battery voltage OR PV voltage > Battery voltage+5v) ?

or is there any other better option ?

 

[Q-Dog]

A Victron MPPT needs only 5 volts above battery voltage to start charging. With your one panel you should have zero issues with a 12 volt setup. With a 24 volt battery the charger may not start on a cloudy day when the battery is nearly full, but do you really need to charge when the battery is nearly full?

I see little reason to use a PWM charge controller ... the MPPT will out perform it in most situations.