Complex sentence: A large number of CNTs are needed to store a significant amount of energy that can be used for macroscopic processes.And in order to achieve such large amount of energy storage the CNT springs must maintain high stiffness and elasticity.
Split into simpler sentences: A large number of CNTs are needed to store a significant amount of energy that can be used for macroscopic processes. In order to achieve such a large amount of energy storage the CNT springs must maintain high stiffness and elasticity.