My original dual battery.
Made a Mavic double battery from the original components. I decided not to disassemble the second battery, plastic in fact plays the role of a protective casing for soft insides. 30 grams of the case and 19 grams of the board will not solve anything for me + -1 minute. I decided to try to fix one on the other. Plus I see in leaving the charge controller with a temperature sensor that turns off charging in which case. That is, they will be charged normally. And also automatically discharge to 50% capacity.
Since I have 4 batteries, I think to make 2 pairs. To fly on single batteries for 10-15 minutes is not convenient.
Donguang (left) and Sunwoda (right) batteries, wire connection:
Holes for wires are also made by heating the file. This is the most accurate way. Before melting the holes, the flat wooden stick needs to move the wires + - so that they do not interfere and do not accidentally melt them. By the way, when cutting a window by heating a thin knife, the cap is put neatly in place, put back on the sealant later. Before the procedure, we land the battery until it turns off for safe soldering and cutting the window.
Soldering is complicated and requires accuracy, I do not advise anyone to do this if there is no experience, but to buy a ready-made battery. The XT60 yellow connector is used for 12V, the T-PLUG red connector is slightly different for balance. Not to be confused and not inserted into each other. 12V 1.5mm2 wire; 0.5mm2 cans. Outside the wires are covered with black tape. Inside the silicone to isolate the solder and hold the wires in case of vibration. The window is closed back with silicone.
Window and holes:
2 Sunwoda batteries, wire connection:
2 doubled batteries:
Plus, in a double battery, I see another one, at a Mavic of 5 km this is the normal range in nature, you fly there on 1 battery and turn sharply just to fly back. On a double one, at a distance of 5 km, you can safely fly, take pictures. Mavic is long-range, but to fly and shoot at this distance with 1 battery is simply unrealistic. We also often have the wind, the battery consumption is much higher, for example, I shot a beautiful church only took off, slowly flew around it and the battery ran out, the flow in the wind was just like in sports and the flight took only 10-15 minutes, I also barely reached the critical landing. With a double if necessary, it will be possible to connect them longer and take pictures further. One day in the fall I flew on tressure island, enjoyed the view of Alcatraz, but as usual in San Francisco the weather is windy. Batteries had to be changed every 15 minutes, it is very small. I just managed to fly along the coast, record the view of San Francisco as the battery ran out. A dual battery will be useful for such filming.
The forecast range, I think the standard is like 20 km of flight without effort minus 1 km per plastic on the battery, I also think over time minus 1 minute per hull, that is, about 25-30 minutes of active flight in sport mode. In one battery Mavic in real weather conditions flies 9-10 km and in sports it is 12-15 minutes of flight. Without plastic on the battery, the original battery would weigh 205 grams with wires, here the weight is 260 grams (battery, connectors and wires). The difference is 55 grams, I do not think that much.
Savchenko on an open original battery weighing 205 grams flies 22 km, with a theoretical margin of 24 km if planted dry. At the same time, the stock remote Mavic in nature took 11 km of range from it.