Enabling silicon microparticles for battery anode applications through novel graphene wrapping and surface coating pathways 

Bor Jang – CEO Global Graphene Group

0:00:00   this conference will now be recorded.
0:00:09   I know my name is Bor Jang. I'm co founder and chief scientist of Global Golfing Group. Today, I'd
0:00:18   like to talk to you about hi silicon content and are active materials for even batteries. As you
0:00:26   know, um, all solid state is a metal battery typically is considered of safer and have higher energy
0:00:35   as compared to the current lithium ion batteries. However, um, all solid state lithium metal
0:00:43   batteries still have some technical issues that need to be addressed and the production equipment
0:00:50   off solid state lithium metal battery is largely distinct from and incomparable with current lithium
0:00:58   ion cells equipment, and that is a major barrier to widespread adoption. And for this reason and
0:01:06   others, um, all solid state lithium metal batteries are considered to be maybe 5 to 8 years away,
0:01:14   particularly if you make use off so called inorganic solid state electoral right. However, currently,
0:01:22   the TV industry is very interested in, um, battery that can provide energy density that go beyond
0:01:32   260 while our peculiar grant, particularly if one can achieve and energy density off 352 maybe 450
0:01:41   while our peculiar Mosul. Then the e V can be can have extended driving range. Okay, so at the
0:01:50   moment, in short, there are some gap existed between Colonel is, um iron battery and huge. All
0:01:59   solicited a terrorist. And we believe that we have some solutions to this problem. So we have
0:02:06   developed some battery technologies that we enable risk free transition to higher energy batteries.
0:02:14   For example, if you take high silicon content, uh, annals, then you can achieve energy density. Much
0:02:23   higher than 301 are procured Graham, and then typically very close to 351 are procured. Graham. Also,
0:02:32   if you pretty she hated your silicon or highly pretty, she ate it. Your silicon you can actually
0:02:38   achieve 450. Wow, procure crime. And then you can make use off existing equipment for producing
0:02:48   these their own batteries. You don't have to change your production line, for example.
0:02:54   But how I can't high silicon content leads them on batteries. Have some technical issues that need
0:03:01   to be addressed us. Well, One of the major issue, of course, is the typical typical erupted capacity
0:03:09   decay problem off silicon based Anil materials and I think, um, everyone knows that the capacity
0:03:19   decay off a silicon annual based. This themselves is typically due to the following reasons one is
0:03:28   trapping off. Listen, irons. For example, during the first, um, one or two cycles, you are
0:03:36   introduced. Your lead them iron from capital to the animal and then build in the subsequent
0:03:42   discharge up to about 10% off the lithium will be trapped inside your silicon, uh, structures. Okay.
0:03:52   Typically in the defects areas, grand boundaries, it's Citrus. And then the second cause for the
0:04:01   rapid capacity decay and a very serious one is the information off solid electoral interface during
0:04:09   the first few cycles. And that, of course, is caused by productive the competition of electoral line,
0:04:16   which actually consumes both active lithium irons and electrolytes. So you will form some so called
0:04:24   S E I film on the surface of here, and that can consume up to 25% more or less, um, off the lesion.
0:04:34   And this is not the end of stories yet. So if you continue to charge and discharge of battery, then
0:04:42   silicon particles can undergo volume expansion, shrinkage, expansion, shrinkage, etcetera and
0:04:50   repeated volume changes will lead to repeat it s Z I breakage and reformation off S C I and that
0:05:00   will continue to consume more liquid electoral I and also more lithium irons. And as you can see
0:05:12   here and then you may say, Well, then I can have quoted silicon particle surface with some carbon.
0:05:19   Yes, you can. And then with that, you can improve the Elektronik conductive ity off your city Kong
0:05:28   particle. All the all the electrical connectivity off the entire annual. Unfortunately, carbon, it's
0:05:34   not very elastic. So during battery charge and charge, for example, this carbon surface would will
0:05:41   be broken. And that will expose, um, silicon again to the electrolyte, and that would again consume
0:05:52   more. Um, these, um, iron and more, um decreed elects. All right, so very briefly, Um, the right
0:06:02   constant context of legally electorate with the ano active materials really is a recipe for failure.
0:06:09   Okay, so So this direct contact weekly electrolyte with the annual active material like second
0:06:15   particle must be minimized or eliminated.
0:06:21   Well, then there is another issue associate with the use of silicon assess the annual active
0:06:28   material in releasing my own battery, and that is the increase in electoral sickness. For example,
0:06:34   if originally you have the thickness, maybe 70 micron to maybe 100 or 200 micro Mosul and then, um,
0:06:45   during, um, recharge off the battery, then you have the following consequences. Your electoral
0:06:55   thickness can be significantly increase and that that is a major issue in the patriot design. Second,
0:07:04   it can also cause interruption off the network electron conducting pathway and also the lithium ion
0:07:11   conducting pathway. And then, of course, without a good binder did your Anil electoral can get
0:07:19   disintegrated, So that's a very serious problem as well. So what can we do in order to reduce this
0:07:28   issue here or eliminated this issue? Well, you can introduce porosity or pours into the silicon
0:07:37   particle waiter is a primary particle or the secondary particle, or you can introduce pull in the
0:07:44   electoral. Okay, So, as you can see here, you silicon particle, you can build in some poor's. So
0:07:52   when, uh, during better recharge, the city can can expand inward. Or it can occupy some of the empty
0:08:01   space, for example. Ideally, of course, and so you can create poles in a primary particle, or you
0:08:09   can create pores in the secondary particle. For example. This is a secondary particle inside which
0:08:14   you have your silicon particle. And then you can introduce pores here. All these poll in the second
0:08:22   inside the secondary particles off course, you have to build some conducting pathway for both
0:08:28   electron And these, um irons also also, you can introduce pores in the electoral and that is shown
0:08:37   here. You can introduce your poll here. Okay, You have to do it. One will another.
0:08:47   All right. So here is the approach. Is that it z three that we do in order Thio mitigate or minimize
0:08:57   the issue off the volume, expansion and repeated formation and destruction of S. C. I. The first
0:09:03   thing that we do is to introduce a so called secondary particle. So inside secondary particle as you,
0:09:09   as I just said, um, in the last slide that that we can introduce the ferocity. We've also introduced
0:09:18   some conducting editor for that that is conducive to the migration of both electron and science. And
0:09:27   then we have encapsulating layer, which basically is graphene based materials. We also had a second
0:09:35   approach that we actually quoted the silicon particle with some elastic parliament and in this case.
0:09:42   Then when silicon expand, this elastic parliament will expand as well in a congruent and come formal
0:09:51   manner when it better be discharged, the second battery shrink. Then this industrial can shrink
0:09:59   accordingly. And therefore you can prevent the city conch particle from contacting the decree
0:10:08   electrolyte continuously. And then we also in addition to this, we also introduced the so called
0:10:16   elastic polymer binder. OK, that can hold a silicon particle much better to prevent disintegration
0:10:25   off the entire electoral.
0:10:30   And so, back in 2000 and seven, we file a serious of patterns related to the graphing supported a
0:10:37   graph in right silicon composite material. This includes both US pattern and international pattern.
0:10:44   And this is the kind of secondary particles that we produce. Uh, during the last 10 years or so mhm
0:10:55   and so in a more details of structure, as you can see that we have seen the mostly right around the
0:11:03   silicon nanoparticles. And then if you look at the internal structure that we have introduced some
0:11:10   ferocity, some pours into the secondary structures already and then off. And then, of course, you
0:11:18   have to, um, be able to prevent the liquid electrolyte from entering the secondary particle and
0:11:26   still allow the lithium irons to go to come in contact with your silicon particles. So you have to
0:11:33   build in some conducting pathways. So very briefly, we have introduced Graphene Shell, um,
0:11:42   encapsulated in the silicon particle that will regulate the silicon expansion. And then we also have
0:11:49   built in poor in the primary and all secondary particle to reduce or eliminate the secondary
0:11:55   particle expansion. Yeah, and we also introduced some, um, graphene sheet inside the secondary
0:12:03   particle toe to serve as part of the three d enabled electron conducting pathway. And we know that
0:12:10   grew up in has very high electrical conductivity, so it will improve the silicon utilization. We
0:12:16   also use the nano silicon particle or silicon little while to ensure high capacity and to avoid
0:12:23   popularization. We had a special way of producing, uh, nanoseconds using some patented technologies.
0:12:33   And, of course, we had a fully own subsidy theory called Taiwan Walking Company that produced coffin
0:12:40   for us.
0:12:42   And here is, uh, some of the technical data associate with our what we call G a silicon high
0:12:51   capacity and of materials. As you can see that our first cycle efficiency exceeds 89% and some of
0:12:59   the products after about 92%. Also, and then our capacity typically eyes from 2000 to 2000 and 800
0:13:10   minimum program also. Okay. And we again, we have problems. Our patented technology that enable
0:13:19   locals production off our narrow silicon. All right, Mhm. And he shown here is, uh, some of the data
0:13:31   askew can see that we can actually wrong for 100 cycles. And that that will, we will be able to
0:13:39   maintain approximately 77% off the original capacity by using this golf in, uh, in calculating there,
0:13:50   um, approach.
0:13:56   And basically, for this particular product, we take graph in silicon and some other ingredient and
0:14:03   then combined together by using some locals high volume production equipment. And not that we can
0:14:11   produce the secondary particles like that. And we are. This is an image of our factory. Here we are.
0:14:18   We had a production capacity, 25 metric tons per year and way plan to expand the production capacity
0:14:28   up to about 1000 metric tons per year by middle of next year. And here are some sm images that
0:14:37   indicate that we were able to produce massive quantity of Silicon Natal while by using some very
0:14:43   unique technique. Okay, The second way Thio minimize the electoral expensive issue and also to
0:14:51   eliminate repeated formation and destruction of S E I, um, is to make use of the so called elastic
0:14:59   iron conducting Parnham according silicon particles and also highly elastic binder. And if you pay
0:15:06   attention to the, uh, better the date off Tesla on September 22 you should have heard that the tests
0:15:17   are indicated that that the local silicon particle, um, is a key thio their low cost and all
0:15:28   materials. And they also mentioned that you need to have elastic iron conducting parliament coating
0:15:34   to protect this citizen particle. And also you need to have highly elastic binder and and then some
0:15:41   electoral designed in order to maintain electoral, um, structural integrity, uh, constant in three.
0:15:50   Um, we have already developed this type of technology as early as 2017 and 2016 and 2017. Okay, as
0:15:59   you can see, that in a Tesla's battery day, this specifically indicate that you need to have some
0:16:06   elastic parliament and that parliament needs to be I'm conducting to stabilize the lead. Silicon
0:16:12   surfaces. You also need to have highly elastic find it. And we have all those technologies us as
0:16:18   early as some, um, 2000 and 16. And we had about approximately 35 years pattern that are already
0:16:27   either issue of pending in all these technologies Here. For example, one of the first pattern was
0:16:36   submitted in March of 2016 by using a customer to call the surface off this silicon particle or
0:16:45   multiple silicon particle and encapsulated multiple silicon particle inside elastic God. Uh huh.
0:16:53   Parliament. Okay. We also had the world's first pattern on highly didactic binder, and and then that
0:17:02   was filed in a early 2017. Also. Okay. And here are some of the data on the, uh, it elastic, um
0:17:17   Colgan Elastic parliament coating on the surface off silicon particle. And as you can see that the,
0:17:24   um the, uh, the cycling behavior is quite stable here. And a very important thing is that during the
0:17:32   1st 67 cycle, also, the so called Colomb IQ efficiency reach very high, very close to 99.5 and then
0:17:43   in in the young 10 cycles. Also, it's it's rich. 99.95% okay by using its customers as the quoting
0:17:53   materials. So by introducing some in calculating layer, we actually are able thio increase the
0:18:04   better resale energy density by approximately 20 up to about 40% ast compared to the current is in
0:18:13   my own battery and yet you can We can also reduce the overall battery caused by fitting up to 20%
0:18:21   also in terms off dollars per kilo are.
0:18:26   And of course, this type of technology with some, um um some energy density increase saved by 25%.
0:18:36   Then, for example, your Tesla s May may be able to drive from San Francisco our way through those
0:18:42   centers. We don't happen to stop Thio, reach out your battery and then if you on a BMW I for you can
0:18:50   drive from believing thio music without having to stop for, um recharging. So, in summary, a high
0:19:02   silicon content anil, for example, including between 60% after 90% silicon can in part high energy
0:19:12   maybe greater than 351 off the kilogram. Um, it can be up to 450 even 501 off the kilogram. If you
0:19:23   fully pre vitiate your silicon, All right. And the cube has developed two approaches to addressing
0:19:31   the issues of repeated SC information and destruction. And we provide a troubling solution, um,
0:19:38   faces and our winning, uh, high capacity silicon and the materials we won the 2018 on d 100 award
0:19:49   and this type of technology fit in existing. Uh, these, um I'm better manufacturing facility. You
0:19:57   don't have to change anything in your manufacturing facilities, and we are ready to expand the
0:20:03   silicon and materials capacities from 25 metric tongue at the moment upto hopefully 1000 metric tons
0:20:12   sometime early next year. And in addition to, um and we also have a wide variety of other DZMM
0:20:22   battery technology. We had a total off more than 320 Highbury us pattern. And many, many Cory, um,
0:20:30   patterns. Thank you very much.
0:20:41   Ready for question?