Sustainable all-solid-state anode-less batteries may become critical for eliminating the challenges in traditional batteries. However, conditioning these batteries is a herculean challenge. In this study, anode-less cells were fabricated with single architectures, Cu/ZnO/Li2.99Ba0.005ClO/LiFePO4 or Cu/Li2O/Li2.99Ba0.005ClO/LiFePO4, and batteries of their off with two and three cells in series. Single- and multiple-cell batteries can undergo electrochemical cycles without requiring applied pressure while operating safely and inexpensively with viable materials at room temperature. All the batteries in this study did not require an inert atmosphere to be fabricated since no lithium metal was used a priori, which is a significant step toward sustainability, cost reduction, and scalability. The single cells featured a Li-anode nucleation layer of ZnO or Li2O doctor bladed on the negative current collector's surface. The maximum voltage accomplished in single cells was 3.2 V (with Li2O). Based on the most favorable capacity performance determined through electrochemical analysis, batteries incorporating two and three cells were assembled and connected in series, each integrating a ZnO layer, which enables the cell to achieve higher energy density. The two-cell battery achieves a maximum capacity of 6 mAh.g−1cathode, corresponding to a lithium discharged thickness of 0.369 μm, a maximum Coulombic efficiency CE of 34 %, almost half the CE of the single cell (76 %). Still, it is able to cycle for 18 cycles which is nearly the same number as a single cell. It is noteworthy that the internal resistance increases Ri,total = Ri,1 + Ri,2, while the capacitance decreases Ceq = C1C2/(C1 + C2), in two, or more, cells in series, in detriment to the capacity of the cell. The batteries, composed of three cells, cycled for 16 cycles to successfully power LEDs of different colors, finally showing a terminal potential of 5.3 V (1.8 V per cell). The groundbreaking finding in this study stems from assembling performing anode-less cells in series, representing a significant step forward in validating the viability of these cells for industrial applications. However, at the present power and energy densities, a long path is left to overcome until these cells are ready to serve in everyday use.