The present invention relates to electrochemical cells, electrodes, and related methods. In some embodiments, a removable filler material may be employed during fabrication of an electrochemical cell, or component thereof, to produce electrochemical devices having improved cell performance and rate capability. Electrochemical cells may exhibit enhanced utilization of electroactive species and/or increased accessibility of electroactive species within the electrochemical cell during operation. In some cases, the invention may provide electrodes which advantageously possess both high loading of an electroactive species (e.g., greater than 1.5 mg/cm2), while also maintaining the stability and good mechanical properties of the electrode.