Lead-free relaxor ferroelectric energy-storage ceramics based on Bi0.5Na0.5TiO3 (BNT) systems are renowned for their exceptional properties, including a high P-max (>40 mu C/cm(2)) and Curie temperature (T-c similar to 320 degrees C). In the pursuit of further enhancing their energy storage characteristics, we have developed a novel series of ceramics, namely (1-x)(Bi0.5Na0.5)(0.7)Sr0.3TiO3-xBa(0.94)La(0.04)Zr(0.02)Ti(0.98)O(3) (x = 0, 0.1, 0.2, 0.3 and 0.4), abbreviated as (1-x)BNST-xBLZT, and assessed its structural and performance attributes. With the introduction of Ba0.94La0.04Zr0.02Ti0.98O3(BLZT), these ceramics retain their characteristic phase structure where tetragonal (T) and rhombohedral (R) phases coexist, effectively disrupting long-range ordered domains and augmenting their energy storage capabilities. Notably, we achieved a remarkable recoverable energy storage density (W-rec) of 3.41 J/cm(3) and an extraordinarily high energy storage efficiency (eta) of 87.33 % in ceramics with x = 0.3 under an electric field of 260 kV/cm. Furthermore, these ceramics exhibit excellent temperature stability (-2 degrees C similar to 228 degrees C), robust cycle stability (10(6) cycles), a substantial discharge energy density (W-d similar to 0.93 J/cm(3)), impressive power density (P-D similar to 39.3 MW/cm(3)), and rapid transient discharge times (t(0.9) similar to 0.14 mu s). In summary, the 0.7BNST-0.3BLZT ceramic demonstrates high power density, rapid charge and discharge rates, and excellent temperature and cyclic stability, positioning it as a promising material for pulse power systems and harsh environments.