Inexpensive and high energy density cathode materials can decrease battery electric vehicle (BEV) cost and increase driving range, which are barriers to consumer adoption. Current state of the art BEV cathode is layered nickel manganese cobalt (NMC) oxide, which acts as the Li source and intercalates Li during discharge. Recently however, Co and Ni prices have skyrocketed due to supply chain challenges, which has increased material supplier costs and BEV prices indirectly. Therefore, next generation cathode materials that are cheap, robust, and long lasting can address cost and energy density limitations faced by NMC. Direct pathways to reduce NMC cost and increase energy density are to utilize materials with lower input costs and operate the cathode material at higher voltages (> 4.5 V). However, when Co or Ni components are substituted for cheap materials (e.g., Mn) their performance can worsen. Similarly, when NMC are operated at higher voltages, the layered structure framework destabilizes, and phase transitions occur. This causes particle cracking, which exposes new surfaces to electrolyte and consumes active material. Clearly, there are tradeoffs for NMC development where low cost leads to low energy density and high voltages lead to poor longevity. In the battery field, rather than only modify NMC, there is interest in developing cathode chemistries that are not restricted by the intrinsic limitations of NMC. To reduce cost, chemistries that contain high contents of Mn and provide high capacity through anionic redox, such as lithium rich (LR), are of interest. Unfortunately, practical use of LR is limited by poor longevity, which has been attributed to voltage fade caused by oxygen release. However, efforts to prevent oxygen release have not improved performance, which raises the question if oxygen release is even the root cause of voltage fade. For high voltage stability, single crystal nickel manganese cobalt oxide (SC) cathodes consist of single grain morphologies that minimize particle cracking and electrolyte exposure. In theory, SC should be able to improve longevity at high voltages, but SC have higher costs due to more complex synthesis. Moreover, reducing Co content would directly lower SC costs, but few studies have discussed Co free SC performance. Although LR and SC can resolve tradeoffs between cost and energy density or energy density and longevity, there are clear knowledge gaps that prevent practical use. In this dissertation, research has been conducted to resolve these knowledge gaps. Chapter 2 describes the use of advanced characterization techniques that span multiple length scales to clarify the origin of oxygen release in LR cathodes and ultimately voltage fade. Irreversible strain accumulation and release due to different redox activity in composite structures was found to be the root cause and strategies to address them are proposed. In chapter 3, the effects of Co removal on SC are investigated to better understand tradeoffs between cost and performance. Interestingly, when Co was removed a LR nano domain formed in SC, which induced particle strain and reduced longevity at high voltages. This also contrasts with NMC where performance at high voltages improved after Co removal. Moreover, these insights from LR and SC have inspired the design of a multi structure NMC (MS-NMC) cathode as described in chapter 4. MS-NMC, integrates cathodes that are redox active, structurally coherent with NMC, and intrinsically stable at high voltages, such as LR or disordered rock salt (DRX), with NMC into one particle. NMC, LR, and DRX are also spatially controlled to reside in the bulk, interlayer, and surface respectively, to optimize their performance contribution. This work is among the first to describe controlled synthesis of multi structure cathodes and serves to inspire pathways to develop other cathode material types. Finally, chapter 5 summarizes the collected results and outlooks for future work are described.