During the development of the first Ecuadorian satellite once mission objectives and payload design was complete, the power budget calculations indicated that we would need a large amount of energy to run the main payload which was a real time video transmission system, our system design guidelines dictated that such power matrix should be robust, redundant and would need a backup system in order to ensure a continuous operation over the longest period of time possible, considering that our solar arrays were composed of solar cells with an efficiency of only 19 percent. We needed a power supply of at least 26.64 Watts per bank, and as per our system safety guidelines the power matrix turned into 4 of this banks, giving a total of 106.56 Watts, the challenge was to pack this much power into an space small enough to fit into a 1U structure. The benefits of having this much power available for the spacecraft became obvious as we calculated the expected life of the power matrix and simulated/tested the illumination-eclipse cycle and charge-discharge periods, thus reducing the load on each cell and maximizing the expected battery life, each array was composed of 16 cells each, and our spacecrafts carry 2 of this arrays on board, also each array uses the waste heat of the spacecraft electronics to warm itself by the use of a carbon nanotubes based thermal transfer system and a micro MLI layer that allows the arrays to avoid radiating this heat back into the neighboring internal electronics. Now after more than 3 years operating in space in 2 spacecrafts, NEE-01 PEGASUS and NEE-02 KRYSAOR, this battery array design has demonstrated to exceed the expectations of the system design guidelines. This paper will describe the system; discuss testing and operation data as well as a new thin design to flight in one upcoming U.S. cubesat mission next year and more follow-up missions of this program.
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