how can I use this LED with batteries?
You should use a constant current boost LED driver.
I used a MT3608 to boost the voltage
The MT3608 product you have is a constant voltage regulator which would require a current limiting resistor or CCR.
Example CCR: ON-Semi NSV50350 350 mA CCR
To use the boost DC-DC converter you have,
you should adjust the output voltage to just over 12V (e.g. 15V)
and add a series current limiting resistor of at least 5 Ω and 3 watts (or CCR).
Measure the voltage at the LED terminals.
Lower the voltage of the MT3608 as close as you can to the LED measured forward voltage.
If using resistor, you may want to recalculate a new value based on the forward voltage and temperature. LEDs should not have a case temperature over 50°C.
I changed the source to one 18650 battery but it doesn’t work.
A single 18650 cell should light this LED at max intensity for an hour or so if using a brand name battery. Charlatan vendors love the battery market. Test your battery with a known load (≈ 1 Amp) and monitor the voltage discharge over time.
You can compare your results to the discharge curve in this datasheet of this middle of the road Panasonic NCR18650 energy cell.
I have a Sumbulbs 12036 LED COB Strip.
Your LED has low luminous efficacy of 100 lumens / Watt.
This 100 lm/W is very likely exaggerated as it is not correctly specified by CCT and CRI.
You could get less heat, more lumens, and longer battery life with a more efficient LED.
Current technology LEDs have a luminous efficacy around 180-220 lm/W (mid-powered strips).
This 7 mm x 7 mm high power Cree XLamp XHP70.2 has more lumens, produces less heat per lumen, and is much more efficient that the LED you selected.
12.8V and current of 520mA. I kept the light turned on a few hours and everything looks ok.
At 600 mA this LED is going to get very hot. It looked ok, but how did it feel? Could you touch it without getting burned?
I mounted an aluminum panel on back to ensure a good heat dissipation.
A flat horizontal aluminum panel will only slow down the rising temperature. Unless the panel is much bigger than the LED you will end up with a very hot LED and a very hot aluminum panel.
Even with a decent heatsink, you will likely need to reduce the current to get the LED temperature under 50°C.
This will also give you longer battery life.
I would recommend a heatsink like this: 4.850" Wide Extruded Aluminum Heatsink cut to a few inches. Cost is $1.16 per inch plus shipping.