The first spatially resolved scattering images for four lithium polymer (Li-po) bat- tery sets of differing thickness (0.5 mm, 1.6 mm, and 2.0 mm) and capacity (15, 43, 50, and 90 mAh) were imaged using X-ray and neutron Talbot-Lau, near- field and far-field interferometry. Despite the worn batteries having over 1500 charge/discharge cycles, the capacities were still above 80%, indicating a well- manufactured battery.
X-ray imaging performed at CAMD utilized the Talbot-Lau and a new interfer- ometry design (near-field) that probed scattering lengths from 20 nm up to 906 nm.
In the 43 mAh batteries, absorption and dark-field images revealed two layers of battery materials with locational scattering between charged and discharged states. Neutron diffraction performed on a Li-po battery revealed a decrease in LiC6
and LiCoO2 peak intensity from a fresh and a worn battery. A statistical analysis
method (Principal Component Analysis/ Multivariate Curve Resolution) was at- tempted to separate battery components using a synthetic dataset and correlate to the diffraction data. While a 7-component PCA system did not behave as an- ticipated, a 3-component system showed a decrease in C6 concentration and an
increase in LiC6 concentration as a function of state of charge. The possibilities
of separating battery components is dependent upon known crystallographic and neutron diffraction information, some of which is unknown for lithium graphite compounds like LiC12, LiC18, and LiC24.
Neutron Bragg edge imaging performed on 2 mm thick 43 mAh batteries revealed changes between the fresh and worn, charged and discharged states. The worn batteries always possessed a higher attenuation signal than the fresh batteries. The most logical explanation is that during lithium intercalation when a battery is charged, the battery swells up to 15% of it’s original volume. When a battery is worn, there is less lithium to migrate between electrodes, thus reducing the signal. Neutron Talbot-Lau interferometry showed spatial differences in the scattering signal at the 1.97 µm scattering range. Vertical features of high scattering in a charged and discharged battery were observed in 0.5 mm thick 15 mAh batteries. However, with only one layer of material in the battery, the signal was relatively weak in comparison to the 2 mm thick batteries.
In a new far-field interferometry experiment, the autocorrelation length, ξ, was probed from 600 nm up to 4.5 µm. The scattering changes dramatically as a function of grating distance D(G1-G2) and autocorrelation length, ξ, between worn
and fresh batteries. While it is unknown as to what is causing this phenomenon, the dark-field images show locations of high scattering near the edges of all batteries. The difference between fresh and worn batteries is seen in the evolution of the average scattering with D(G1-G2) values. When the G1-G2 distance was small (between 3 - 10 mm), harmonics generated from the gratings were projected onto the battery images. At large grating distances (above 30 mm), the dark-field signal turned negative in all batteries, indicating a design flaw in the setup. To understand the difference between fresh and worn batteries, the average scattering signal was plotted as a function of grating distance. The plots for the 43 mAh batteries show a maximum scattering signal for the worn battery at 18 mm, the slightly worn battery at 24 mm, and the fresh battery at 27 mm.
References
[1] Goldberg, B.S., Hausser, A.G., Le, B.T. (1983) Accelerated cycle life testing of lead-acid golf car batteries and the influence of separator type on battery life, energy consumption and operating cost. J. Power Sources 10(2): 137–48. [2] Thomas, F., Mills, G., Howe, R., Zobell, J. (2012) Lithium battery fires: im-
plications for air medical transport. Air Med. J. 31(5): 242–248.
[3] Sullivan, J.L., Gaines, L. (2012) Status of life cycle inventories for batteries. Energy Convers. Manage. 58: 134–148.
[4] Schweikert, N., Hofmann, A., Schulz, M., Scheuermann, M., Boles, S.T., Hane- mann, T., Hahn, H., Indris, S. (2013) Suppressed lithium dendrite growth in lithium batteries using ionic liquid electrolytes: Investigation by electro- chemical impedance spectroscopy, scanning electron microscopy and in situ 7li nuclear magnetic resonance spectroscopy. J. Power Sources 228: 237–243. [5] Wang, D., Zhang, W., Zheng, W., Cui, X., Rojo, T., Zhang, Q. (2017) Towards high-safe lithium metal anodes: Suppressing lithium dendrites via tuning sur- face energy. Adv. Sci. 4(1): 1600168.
[6] Tang, Q., Li, H., Zuo, M., Zhang, J., Huang, Y., Bai, P., Xu, J., Zhou, K. (2016) Optimized assembly of micro-/meso-/macroporous carbon for lis bat- teries. Nano 12(02): 1750021.
[7] Feng, N., He, P., Zhou, H. (2016) Critical challenges in rechargeable aprotic lio2 batteries. Adv. Energy Mater. 6(9): 1502303–n/a.
[8] Li, Q., Chen, J., Fan, L., Kong, X., Lu, Y. (2016) Progress in electrolytes for rechargeable li-based batteries and beyond. Green Energ. Environ. 1(1): 18–42.
[9] Younesi, R., Veith, G.M., Johansson, P., Edstrom, K., Vegge, T. (2015) Lithium salts for advanced lithium batteries: Li-metal, li-o2, and li-s. En- ergy Environ. Sci. 8(7): 1905–1922.
[10] Liu, K., Zhuo, D., Lee, H.W., Liu, W., Lin, D., Lu, Y., Cui, Y. (2017) Ex- tending the life of lithium-based rechargeable batteries by reaction of lithium dendrites with a novel silica nanoparticle sandwiched separator. Adv. Mater.
29(4): n/a.
[11] Aravindan, V., Gnanaraj, J., Madhavi, S., Liu, H.K. (2011) Lithium-ion con- ducting electrolyte salts for lithium batteries. Chem. Eur. J. 17(51): 14326– 14346.
[12] Kang, D.W., Kim, J.K. (2016) Characterization of fibrous gel polymer elec- trolyte for lithium polymer batteries with enhanced electrochemical proper- ties. J. Electroanal. Chem. 775: 37–42.
[13] He, Y.B., Li, B., Yang, Q.H., Du, H., Kang, F., Ling, G.W., Tang, Z.Y. (2011) Effects of current densities on the formation of licoo2/graphite lithium ion battery. J. Solid State Electrochem. 15(9): 1977–1985.
[14] Wen, J., Yu, Y., Chen, C. (2012) A review on lithium-ion batteries safety issues: existing problems and possible solutions. Mater. Express 2(3): 197– 212.
[15] Lin, C.K., Ren, Y., Amine, K., Qin, Y., Chen, Z. (2013) In situ high-energy x-ray diffraction to study overcharge abuse of 18650-size lithium-ion battery. J. Power Sources 230: 32–37.
[16] Kumai, K., Miyashiro, H., Kobayashi, Y., Takei, K., Ishikawa, R. (1999) Gas generation mechanism due to electrolyte decomposition in commercial lithium-ion cell. J. Power Sources 81-82: 715–719.
[17] Abraham, D.P., Roth, E.P., Kostecki, R., McCarthy, K., MacLaren, S., Doughty, D.H. (2006) Diagnostic examination of thermally abused high-power lithium-ion cells. J. Power Sources 161(1): 648–657.
[18] Gao, M., Liu, N., Li, Z., Wang, W., Li, C., Zhang, H., Chen, Y., Yu, Z., Huang, Y. (2014) A gelatin-based sol-gel procedure to synthesize the lifepo4/c nanocomposite for lithium ion batteries. Solid State Ionics 258: 8–12. [19] Choi, S.H., Kim, J., Yoon, Y.S. (2004) Self-discharge analysis of licoo2 for
lithium batteries. J. Power Sources 138(1-2): 283–287.
[20] Emery, N., Herold, C., Lagrange, P. (2008) Overview on the intercalation reactions of lithium alloys into graphite. Prog. Solid State Chem. 36(3): 213– 222.
[21] Goodenough, J.B., Kim, Y. (2010) Challenges for rechargeable li batteries. Chem. Mater. 22(3): 587–603.
[22] Siegel, J.B., Lin, X., Stefanopoulou, A.G., Hussey, D.S., Jacobson, D.L., Gor- sich, D. (2011) Neutron imaging of lithium concentration in lfp pouch cell battery. J. Electrochem. Soc. 158(5): A523–A529.
[23] Gummow, R.J., Sharma, N., Peterson, V.K., He, Y. (2012) Synthesis, struc- ture, and electrochemical performance of magnesium-substituted lithium man- ganese orthosilicate cathode materials for lithium-ion batteries. J. Power Sources 197: 231–237.
[24] Garlea, E., King, M.O., Galloway, E.C., Boyd, T.L., Smyrl, N.R., Bilheux, H.Z., Santodonato, L.J., Morrell, J.S., Leckey, J.H. (2017) Identification of lithium hydride and its hydrolysis products with neutron imaging. J. Nucl. Mater. 485: 147–153.
[25] Cai, L., An, K., Feng, Z., Liang, C., Harris, S.J. (2013) In-situ observation of inhomogeneous degradation in large format li-ion cells by neutron diffraction. J. Power Sources 236: 163–168.
[26] Hofmann, M., Gilles, R., Gao, Y., Rijssenbeek, J.T., Muehlbauer, M.J. (2012) Spatially resolved phase analysis in sodium metal halide batteries: neutron diffraction and tomography. J. Electrochem. Soc. 159(11): A1827–A1833. [27] Senyshyn, A., Muehlbauer, M.J., Dolotko, O., Hofmann, M., Pirling, T.,
Ehrenberg, H. (2014) Spatially resolved in operando neutron scattering studies on li-ion batteries. J. Power Sources 245: 678–683.
[28] Rodriguez, M.A., Ingersoll, D., Vogel, S.C., Williams, D.J. (2004) Simultane- ous in situ neutron diffraction studies of the anode and cathode in a lithium- ion cell. Electrochem. Solid-State Lett. 7(1): A8–A10.
[29] Wang, X.L., An, K., Cai, L., Feng, Z., Nagler, S.E., Daniel, C., Rhodes, K.J., Stoica, A.D., Skorpenske, H.D., Liang, C., Zhang, W., Kim, J., Qi, Y., Harris, S.J. (2012) Visualizing the chemistry and structure dynamics in lithium-ion batteries by in-situ neutron diffraction. Sci. Rep. 2: 747.
[30] Wehrens, R.: Chemometrics With R: Multivariate Data Analysis in the Nat- ural Sciences and Life Sciences. Springer, Heidelberg (2011).
[31] Jaumot, J., Tauler, R. (2010) Mcr-bands: A user friendly matlab program for the evaluation of rotation ambiguities in multivariate curve resolution. Chemometr. Intell. Lab. 103(2): 96–107.
[32] Kardjilov, N., Hilger, A., Manke, I., Griesche, A., Banhart, J. (2015) Imaging with cold neutrons at the conrad-2 facility. Phys. Procedia 69(Proceedings of the 10th World Conference on Neutron Radiography (WCNR-10), 2014): 60–66.
[33] Kardjilov, N., Hilger, A., Manke, I., Woracek, R., Banhart, J. (2016) Conrad- 2: the new neutron imaging instrument at the helmholtz-zentrum berlin. J. Appl. Crystallogr. 49(1): 195–202.
[34] Wen, H., Bennett, E.E., Hegedus, M.M., Rapacchi, S. (2009) Fourier x-ray scattering radiography yields bone structural information. Radiology 251(3): 910–8.
[35] Marathe, S., Assoufid, L., Xiao, X., Ham, K., Johnson, W.W., Butler, L.G. (2014) Improved algorithm for processing grating-based phase contrast inter- ferometry image sets. Rev. Sci. Instrum. 85(1): art. no. 013704.
[36] Van Aarle, W., Palenstijn, W.J., De Beenhouwer, J., Altantzis, T., Bals, S., Batenburg, K.J., Sijbers, J. (2015) The astra toolbox: A platform for advanced algorithm development in electron tomography. Ultramicroscopy 157: 35–47. [37] Butler, L.G., Schillinger, B., Ham, K., Dobbins, T.A., Liu, P., Vajo, J.J. (2011) Neutron imaging of a commercial li-ion battery during discharge: Application of monochromatic imaging and polychromatic dynamic tomography. Nucl. Instrum. Methods Phys. Res., Sect. A 651(1): 320–328.
[38] Kino, K., Yonemura, M., Kiyanagi, Y., Ishikawa, Y., Parker, J.D., Tanimori, T., Kamiyama, T. (2015) First imaging experiment of a lithium ion battery by a pulsed neutron beam at j-parc/mlf/bl09. Phys. Procedia 69: 612–618.