The iTPC upgrade for BES-II

STAR has proposed to upgrade the inner sectors of the STAR TPC to increase the segmentation on the inner padplane and to renew the inner sector wires. The upgrade will provide better momentum resolution, better \textit{dE/dx} resolution and, most importantly, it will provide improved acceptance at high rapidity to \textbar $\eta $\textbar $\le $ 1.5 compared to the current TPC configuration of \textbar $\eta $\textbar $\le $ 1 and to extend the pt coverage towards lower pt. The enhanced measurement capabilities of STAR after the iTPC upgrade are a vital part of the BES-II effort for 2019-2020. The expanded rapidity coverage provides a major benefit for many analyses, especially those sensitive to changes in correlation lengths near a critical point, like the net-proton Kurtosis which exhibits interesting energy trends that only appear near the edge of the current STAR acceptance. In the area of dielectron measurements it reduces hadron contamination from a dominant source of uncertainty to an expected statistical uncertainty of only 10{\%}, and will enable significantly improved understanding of in-medium modifications. In this talk I will discuss the physics impact and give a technical overview of the detector upgrade.