As battery-driven systems, e-textiles need battery-efficient power management schemes for increasing the time of the operations. We present a novel power management scheme for e-textiles, which focuses on a battery selection model based on the dependable infrastructures of the token grid communication networks and the flexible power networks (FPN). In the FPN, a power consuming node (PCN) can attain power energy from one of the multiple battery nodes, while the PCNs are interconnected into the e-textile token grid network able to preserve the full-connectivity in the case of faults. By decomposing the battery-efficient model into the Transaction Efficiency for each battery selection transaction, the selection model proposed in this paper aims to achieve high Transaction Efficiency to extend the lifetime of the e-textile applications. Simulation results show that significant lifetime extensions can be obtained with respect to conventional sequential discharge policy.