(327h) Going Beyond Intercalation Capacity of Aqueous Batteries By Exploiting the Conversion Reactions of Mn and Zn-Based Electrodes for Energy Dense Applications
AIChE Annual Meeting
2019
2019 AIChE Annual Meeting
Engineering Sciences and Fundamentals
Electrochemical Fundamentals: Faculty Candidate Session
Tuesday, November 12, 2019 - 2:15pm to 2:30pm
GOING BEYOND INTERCALATION CAPACITY OF AQUEOUS BATTERIES BY EXPLOITING
THE CONVERSION REACTIONS OF Mn AND Zn-BASED
ELECTRODES FOR ENERGY DENSE APPLICATIONS
Dr. Gautam G. Yadav
The current landscape of energy storage systems is dominated
by lithium-ion batteries because of their high energy densities, and continuous
improvement in performance through the last few decades for use in a number of
applications. They certainly have been a boon for rapid societal development;
however, they also have had major disadvantages like high cost, severe
toxicity, high chances of flammability and ethical concerns about the use of
cobalt. Aqueous batteries containing Mn and Zn have the theoretical capacities
to deliver high energy densities comparable to some variations of lithium-ion
batteries, have low cost and toxicity, and high material abundance to be used
as an alternative battery compared to the current status quo. However, Mn and
Zn have been highly irreversible and accessing close to their theoretical
capacities has been very challenging. The current status quo in aqueous
batteries has been to intercalate Zn and H-ions into layered structures to
deliver modest capacities, which also has unfortunately resulted in limited
energy densities.
These layered
structures, although novel, face limitations like their layered counterparts in
lithium (Li)-ion batteries, where the capacity is limited to the hosts intercalation
capacity.
In this talk, we propose a new strategy in
enabling new generation of energy dense aqueous-based batteries, where we
exploit the conversion reactions of rock salt/spinel manganese oxides and
carbon nanotube-nested nanosized Zn electrodes to
extract significantly higher capacity compared to intercalation systems.
Accessing the conversion reactions allows us to achieve high capacities of 750 mAh/g (~30 mAh/cm2)
from manganese oxide (MnO) and 810 mAh/g (~30 mAh/cm2)
from nanoscale Zn anodes, respectively. The high areal capacities help to
attain unprecedented energy densities of 210 Wh/L-cell
and 320 Wh/kg-total (398 Wh/kg-active)
from aqueous MnO|CNT-Zn batteries, which allows an
assessment of its viable use in a small-scale automobile