TY  - JOUR
AU  - Zoller, Florian
AU  - Böhm, Daniel
AU  - Luxa, Jan
AU  - Döblinger, Markus
AU  - Sofer, Zdenek
AU  - Semenenko, Dmitri A.
AU  - Bein, Thomas
AU  - Fattakhova, Dina
TI  - Freestanding LiFe0. 2Mn0. 8PO4/rGO nanocomposites as high energy density fast charging cathodes for lithium-ion batteries
JO  - Materials today
VL  - 16
SN  - 2468-6069
CY  - Amsterdam [u.a.]
PB  - Elsevier Ltd.
M1  - FZJ-2020-02099
SP  - 100416
PY  - 2020
AB  - Freestanding electrodes for lithium ion batteries are considered as a promising option to increase the total gravimetric energy density of the cells due to a decreased weight of electrochemically inactive materials. We report a simple procedure for the fabrication of freestanding LiFe0.2Mn0.8PO4 (LFMP)/rGO electrodes with a very high loading of active material of 83 wt%, high total loading of up to 8 mg cm−2, high energy density, excellent cycling stability and at the same time very fast charging rate, with a total performance significantly exceeding the values reported in the literature. The keys to the improved electrode performance are optimization of LFMP nanoparticles via nanoscaling and doping; the use of graphene oxide (GO) with its high concentration of surface functional groups favoring the adhesion of high amounts of LFMP nanoparticles, and freeze-casting of the GO-based nanocomposites to prevent the morphology collapse and provide a unique fluffy open microstructure of the freestanding electrodes. The rate and the cycling performance of the obtained freestanding electrodes are superior compared to their Al-foil coated equivalents, especially when calculated for the entire weight of the electrode, due to the extremely reduced content of electrochemically inactive material (17 wt% of electrochemically inactive material in case of the freestanding compared to 90 wt% for the Al-foil based electrode), resulting in 120 mAh g−1electrode in contrast to 10 mAh g−1electrode at 0.2 C. The electrochemical performance of the freestanding LFMP/rGO electrodes is also considerably better than the values reported in literature for freestanding LFMP and LMP composites, and can even keep up with those of LFP-based analogues. The freestanding LFMP/rGO reported in this work is additionally attractive due to its high gravimetric energy density (604 Wh kg−1LFMP at 0.2C). The obtained results demonstrate the advantage of freestanding LiFe0.2Mn0.8PO4/rGO electrodes and their great potential for applications in lithium ion batteries.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000539083500022
DO  - DOI:10.1016/j.mtener.2020.100416
UR  - https://juser.fz-juelich.de/record/877276
ER  -