Adding additional battery capacity to my AC200 from my Ecoflow EF1500 battery(s) using a step up converter from 24 to 48 volts. IT WORKS. I got a rock steady 573- 575 watts of incoming charge power into my AC200. With my (2) EF1500 batteries this will give my AC200 a usuable 4100 watt hours of battery capacity.
I started at 11% and ended at 92%. The AC200 received 1300 watts of incoming charge which is 83% of the advertised 1574 watt hours from the battery. Not bad considering the step up conversion and charging losses. This set up should work with any 24 volt batteries. The step up converter is also offered in 12 volt incoming voltage versions as well so it should be feasible to connect that unit directly to a vehicle battery and have fast car charging while traveling.
I purchased the step up converter (link below) through amazon and made a cable by purchasing a clothers drier cord from Lowes. The cable had (4) 10 ga wires inside a single sleeve and already had 4 ring connections crimped on one end. I cut the cable to about 30", added two ring connectors to the red and black wires on the other end of the cable (to attach to the EF1500 24 volt battery output) and soldered an XT90 connector to the two remaining wires. This XT90 is what I connect the AC200’s XT90 to Aviation input cable to and then to the AC200. The four wires with pre-crimped ring terminals attach to the votage step up converter. This gave me a single cable with minimal effort to build and kept the cable short and simple.
Even though the step up converter says it is capable of 20 amps output at 48 volts the Bluetti AC200 limits charging input to 12 amps.
That is why I am only getting 575 watts rather than the max of 700. In any case, 575 watts is plenty for my purpose of extending the battery capacity of my AC200. The converter has been running for about 90 minutes and while warm to the touch, is in no way hot. There is no fan and the unit is silent.
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