Modular Multifunctional Composite Structure for CubeSat Applications: Preliminary Design and Structural Analysis

Abstract

CubeSats usually adopt aluminum alloys for primary structures, and a number of studies exist on Carbon Fiber Reinforced Plastic (CFRP) primary structures. The internal volume of a spacecraft is usually occupied by battery arrays, reducing the volume available to the payload. In this paper, a CFRP structural/battery array configuration has been designed in order to integrate the electrical power system with the spacecraft bus primary structure. The configuration has been designed according to the modular design philosophy introduced in the AraMiS project. The structure fits on an external face of a 1U CubeSat. Its external side houses two solar cells and the opposite side houses power system circuitry. An innovative cellular structure concept has been adopted and a set of commercial LiPo batteries has been embedded between two CFRP panels and spaced out with CFRP ribs. Compatibility with launch mechanical loads and vibrations has been shown with a finite element analysis. The results suggest that, even with a low degree of structural integration applied to a composite structural battery, more volume and mass can be made available for the payload, with respect to traditional, functionally separated structures employing aluminum alloy. The low degree of integration is introduced to allow the use of relatively cheap and commercial-off-the-shelf components.

Energy Storage Structural Composites with Integrated Lithium‐Ion Batteries: A Review

“…Energy storage structural sandwich composites have been fabricated by placing lithium‐ion or LiPo batteries in the core between the laminated face skins. [ 1,4,5,16,47,48,58–69 ] As with laminates, wet hand‐layup or vacuum assisted resin infusion are often used to fabricate the sandwich composites to avoid damage to the batteries. Prior to assembly, battery‐sized cut‐outs are made in the core material to create space to insert the batteries, as shown in Figure .…”

“…[ 88 ] Combining the functionality of these elements presents an opportunity to reduce spacecraft mass that can result in increased mission performance and/or reduced mission costs. Significant space savings can also be achieved by integrating batteries within a volume occupied by structural elements, as demonstrated for a small cube satellite [ 4 ] (Figure 18c).…”

“…Among the various fiber reinforced composites, carbon fiber reinforced polymers (CFRP) are commonly used for making light‐weight structural components due to their high specific strength and stiffness. Further weight reduction can be achieved by combining composite materials (for high mechanical properties) with lithium‐ion batteries (for generation and storage of electrical energy), with potential applications in automotive, [ 1 ] aircraft, [ 2 ] spacecraft, [ 3,4 ] marine, [ 5 ] and sports equipment. [ 6 ] A new generation of high capacity lithium‐ion batteries is rapidly gaining popularity in a variety of industries, including automotive.…”

Structural Batteries for Aeronautic Applications—State of the Art, Research Gaps and Technology Development Needs

“…It was the first [30] and remains the most widely investigated approach. Considered applications are unmanned vehicles [30][31][32], the automotive industry [21], aeronautic industry [33], and maritime sector [18], as well as for space technology [17,34,35], especially microsatellite applications [36,37]. The integration of commercial Li-ion batteries into a dedicated structural element, as shown in Figure 3, presents the lowest degree of multifunctionality.…”

Structural ceramic batteries using an earth-abundant inorganic waterglass binder

“…Diverse approaches have been investigated in pursuit of practical structural energy storage systems. One strategy is to transfer the load to embedded commercial batteries 6 , 7 as well as conventional battery electrodes and current collectors 8 , 9 . In developing multifunctional materials, structurally robust carbon and glass fiber manufacturing methods have been adapted to produce structural capacitor electrodes, 10 – 12 electrolytes, 13 – 15 , and full devices.…”