1 00:00:04,120 --> 00:00:07,040 This is Geology Bites with Oliver Strumpel. 2 00:00:08,400 --> 00:00:11,800 Electric batteries play a central role in our transition 3 00:00:11,800 --> 00:00:16,079 away from fossil fuels. First, we need shipping 4 00:00:16,079 --> 00:00:20,600 container sized grid scale batteries to even out the peaks 5 00:00:20,600 --> 00:00:24,760 and troughs of renewable energy sources such as solar and wind, 6 00:00:25,240 --> 00:00:28,920 and match the supply of electricity to demand even when 7 00:00:28,920 --> 00:00:31,800 the sun is not shining and the wind is not blowing. 8 00:00:33,040 --> 00:00:37,080 Second, we need batteries for electric vehicles, which we're 9 00:00:37,080 --> 00:00:40,160 now producing at a rate of about 15,000,000 a year. 10 00:00:41,680 --> 00:00:44,920 The batteries that make all this possible are lithium ion 11 00:00:44,920 --> 00:00:49,160 batteries, so-called because they store energy by moving 12 00:00:49,160 --> 00:00:52,720 lithium ions between the batteries electrodes during 13 00:00:52,720 --> 00:00:56,880 charge from the cathode to the anode and during discharge from 14 00:00:56,880 --> 00:01:02,640 the anode back to the cathode. But in addition to lithium, four 15 00:01:02,640 --> 00:01:05,880 other metals are critical ingredients of modern lithium 16 00:01:05,880 --> 00:01:11,680 ion batteries, copper, nickel, cobalt, and manganese. 17 00:01:12,840 --> 00:01:16,680 Where do we find these metals, and what geological processes 18 00:01:16,680 --> 00:01:19,480 concentrate them into economically significant 19 00:01:19,480 --> 00:01:24,000 deposits? Adam Simon studies the chemical 20 00:01:24,000 --> 00:01:27,400 and physical processes that affect the mobility of elements 21 00:01:27,400 --> 00:01:31,480 in geological systems and is especially interested in how 22 00:01:31,480 --> 00:01:35,200 mineral deposits form. He is a professor of economic 23 00:01:35,200 --> 00:01:37,320 geology at the University of Michigan. 24 00:01:38,320 --> 00:01:40,880 Adam Simon, welcome to Geology. Bytes. 25 00:01:41,160 --> 00:01:44,200 Thank you, Oliver. Batteries have 4 main 26 00:01:44,200 --> 00:01:48,320 components, the anode, the cathode, the electrolyte in 27 00:01:48,320 --> 00:01:52,360 which they are must, and a separator to separate the anode 28 00:01:52,360 --> 00:01:55,600 from the cathode. I said that lithium is in the 29 00:01:55,600 --> 00:01:59,080 electrolyte, but where are the other four critical metals 30 00:01:59,080 --> 00:02:01,920 needed? It's the cathode that is 31 00:02:01,920 --> 00:02:05,160 important and that's the focus of our discussion today because 32 00:02:05,160 --> 00:02:07,320 there are different types of cathodes. 33 00:02:07,640 --> 00:02:10,080 Each is composed of different types of metal. 34 00:02:10,199 --> 00:02:14,720 Lithium cobalt oxide cathodes, Lithium manganese oxide 35 00:02:14,720 --> 00:02:17,320 cathodes. The metals that are used to make 36 00:02:17,320 --> 00:02:21,520 the cathodes play a role in how much energy the battery can 37 00:02:21,520 --> 00:02:25,000 store and how quickly the battery can give up that energy 38 00:02:25,000 --> 00:02:28,200 to our devices. So the nickel, cobalt and 39 00:02:28,200 --> 00:02:31,440 manganese are ingredients of the cathode, yes. 40 00:02:31,480 --> 00:02:35,280 OK, let's start by talking about the role that lithium and the 41 00:02:35,280 --> 00:02:39,000 other 4 metals actually play during the battery's operation. 42 00:02:40,080 --> 00:02:44,680 Singly charged lithium Li plus is the ion that travels back and 43 00:02:44,680 --> 00:02:47,640 forth between the electrodes during the charge discharge 44 00:02:47,640 --> 00:02:50,520 cycle. Why do we use lithium ions? 45 00:02:50,840 --> 00:02:53,960 Lithium is the lightest solid metal in nature. 46 00:02:54,560 --> 00:02:57,200 It has three protons and three electrons. 47 00:02:57,560 --> 00:03:01,240 Two of these electrons are held very tightly to the nucleus. 48 00:03:01,640 --> 00:03:05,160 But lithium is happy to give up this third electron and become a 49 00:03:05,160 --> 00:03:09,480 positively charged ion. And we refer to this tendency 50 00:03:09,480 --> 00:03:12,440 for lithium to give up this third electron as saying that it 51 00:03:12,440 --> 00:03:15,000 has a very high electrochemical potential. 52 00:03:15,720 --> 00:03:19,080 That, combined with its lightweight, means that lithium 53 00:03:19,080 --> 00:03:23,120 can store a lot of energy in a very small mass, and that's what 54 00:03:23,120 --> 00:03:27,000 makes it ideal for batteries. And the copper, is it playing 55 00:03:27,000 --> 00:03:29,760 the role of a good conductor on one of the electrodes? 56 00:03:29,920 --> 00:03:32,680 Absolutely. So copper is an excellent 57 00:03:32,680 --> 00:03:35,200 electrical conductor, second only to silver. 58 00:03:35,200 --> 00:03:38,160 And copper is also very resistant to oxidation. 59 00:03:38,520 --> 00:03:42,360 So we refer to the copper foil in the battery as a current 60 00:03:42,360 --> 00:03:45,800 collector. It's fused to the graphite anode 61 00:03:45,800 --> 00:03:49,920 and it provides a highly conductive pathway for electrons 62 00:03:50,240 --> 00:03:53,800 to travel from the graphite anode to the external circuit. 63 00:03:54,240 --> 00:03:58,960 And this is the electricity that flows within the battery during 64 00:03:58,960 --> 00:04:01,600 discharging, that powers our devices. 65 00:04:02,000 --> 00:04:05,640 And then in reverse, it's the electricity that we add to the 66 00:04:05,640 --> 00:04:07,800 battery when we recharge the battery. 67 00:04:08,360 --> 00:04:11,600 And there's a lot of copper in lithium ion batteries. 68 00:04:11,800 --> 00:04:15,360 The average electric vehicle, if we sum all of the copper in the 69 00:04:15,360 --> 00:04:18,519 battery, it's about 20 kilograms of copper. 70 00:04:18,839 --> 00:04:22,120 And that's just the copper in the battery, not the copper in 71 00:04:22,120 --> 00:04:24,720 the motor and the wiring systems, which of course is a 72 00:04:24,720 --> 00:04:25,880 lot. More copper. 73 00:04:26,160 --> 00:04:30,880 OK, let's talk about the other three metals, nickel, cobalt and 74 00:04:30,880 --> 00:04:34,480 manganese. What role do they play when the 75 00:04:34,480 --> 00:04:38,000 battery is being used? Nickel provides a very high 76 00:04:38,000 --> 00:04:41,640 energy density that has to do with the oxidation reduction 77 00:04:41,640 --> 00:04:44,320 processes of nickel within the cathode. 78 00:04:44,720 --> 00:04:49,240 So within the cathode, nickel is bonded with oxygen and when a 79 00:04:49,240 --> 00:04:53,960 battery is discharged and charged, electrons are moving 80 00:04:53,960 --> 00:04:59,280 into and out of the cathode. And that is facilitated by 81 00:04:59,280 --> 00:05:02,800 nickel moving back and forth from 1 oxidation state to 82 00:05:02,800 --> 00:05:05,800 another. And nickel's ability to do that 83 00:05:06,040 --> 00:05:10,520 allows it to store a lot of energy in the form of that 84 00:05:10,520 --> 00:05:12,760 electron transfer. What about cobalt? 85 00:05:12,960 --> 00:05:18,520 So cobalt also provides very high energy density and Cobalt's 86 00:05:18,520 --> 00:05:21,960 electronic structure, meaning its ability to give up and to 87 00:05:21,960 --> 00:05:25,880 receive electrons during discharging and charging, allows 88 00:05:25,880 --> 00:05:29,920 for batteries to be charged very rapidly and for batteries to 89 00:05:29,920 --> 00:05:31,680 have very good thermal stability. 90 00:05:32,200 --> 00:05:35,400 Most batteries today, depending on the ratio of nickel to 91 00:05:35,400 --> 00:05:39,520 cobalt, have somewhere on the order of 8kg of cobalt. 92 00:05:39,680 --> 00:05:43,880 So does the cobalt function in conjunction with the nickel in 93 00:05:43,880 --> 00:05:46,160 the cathode, or are they involved with two separate 94 00:05:46,160 --> 00:05:49,880 processes that coexist? Cobalt, when it is bonded with 95 00:05:49,880 --> 00:05:53,200 nickel and manganese in a battery, what we call an NMCA, 96 00:05:53,200 --> 00:05:57,320 nickel, manganese, cobalt battery, the cobalt atoms as 97 00:05:57,320 --> 00:06:01,360 well as the nickel atoms and the manganese atoms are gaining and 98 00:06:01,360 --> 00:06:04,600 losing electrons during discharge and charge. 99 00:06:05,000 --> 00:06:09,160 And so cobalt, similar to what we described for nickel, its 100 00:06:09,160 --> 00:06:14,720 ability to gain electrons and lose electrons, that allows the 101 00:06:14,720 --> 00:06:17,960 cathode that contains cobalt to store a lot of that energy. 102 00:06:18,240 --> 00:06:21,440 Is there a similar story then with the manganese that you have 103 00:06:21,440 --> 00:06:23,040 in a cathode? Exactly. 104 00:06:23,040 --> 00:06:27,240 So manganese is used because it improves a battery's resistance 105 00:06:27,240 --> 00:06:29,840 to overheating during charging and discharging. 106 00:06:30,360 --> 00:06:33,560 And your listeners may have heard about thermal runaway or 107 00:06:33,560 --> 00:06:36,200 lithium ion batteries that can catch fire. 108 00:06:36,760 --> 00:06:40,440 So what happens during thermal runaway is there's a short 109 00:06:40,440 --> 00:06:44,160 circuit that occurs within the battery that can result in 110 00:06:44,160 --> 00:06:47,480 melting the battery and possibly causing the battery to catch 111 00:06:47,480 --> 00:06:50,360 fire. And This is why batteries in a 112 00:06:50,360 --> 00:06:54,640 lot of technologies, for example in laptops, have fans that 113 00:06:54,640 --> 00:06:58,200 remove the heat generated during charging and discharging of the 114 00:06:58,200 --> 00:07:01,240 batteries. And is it the manganese then 115 00:07:01,360 --> 00:07:04,800 that is really the determinant of the maximum safe charging 116 00:07:04,800 --> 00:07:07,200 rate for a battery? So the maximum safe charging 117 00:07:07,200 --> 00:07:11,000 rate will vary according to the metals that are used in the 118 00:07:11,000 --> 00:07:13,640 cathode. So in a nickel, manganese, 119 00:07:13,640 --> 00:07:16,240 cobalt battery, manganese plays a role. 120 00:07:16,520 --> 00:07:20,640 But in each battery, even cobalt free batteries, they have their 121 00:07:20,640 --> 00:07:25,600 own charge discharge rate and that's dictated by the metal 122 00:07:25,600 --> 00:07:29,040 composition of the cathode. We should mention that graphite 123 00:07:29,040 --> 00:07:31,520 is also needed for a lithium ion battery. 124 00:07:32,040 --> 00:07:33,800 Correct. Graphite. 125 00:07:33,880 --> 00:07:35,680 It's a crystalline form of carbon. 126 00:07:36,080 --> 00:07:39,640 It has a perfectly ordered layered crystal structure, which 127 00:07:39,640 --> 00:07:44,680 means that all of the carbon atoms are very strongly bonded 128 00:07:44,680 --> 00:07:49,920 to each other within the sheets and weakly bonded between the 129 00:07:49,920 --> 00:07:53,840 sheets. And this allows lithium ions to 130 00:07:53,840 --> 00:07:59,720 easily move into and between the sheets of graphite in a process 131 00:07:59,720 --> 00:08:02,120 that's referred to as intercalation. 132 00:08:02,600 --> 00:08:07,440 And when we charge our battery, lithium ions move in between 133 00:08:07,440 --> 00:08:11,760 these sheets of graphite. They pull an electron from the 134 00:08:11,760 --> 00:08:14,000 circuit. So the electron flows from the 135 00:08:14,000 --> 00:08:17,840 circuit through the copper, through the graphite to lithium 136 00:08:17,840 --> 00:08:22,400 ions, where the lithium ions then are reduced from a lithium 137 00:08:22,400 --> 00:08:27,120 1 plus to lithium metal. And graphite holds those lithium 138 00:08:27,120 --> 00:08:32,799 ions until we open the circuit to use the energy, and then 139 00:08:32,799 --> 00:08:37,120 graphite allows the lithium ions to move out of those sheets. 140 00:08:37,640 --> 00:08:40,080 OK. Let's move on to the mineralogy 141 00:08:40,080 --> 00:08:43,520 and geological origin of the battery critical metals, 142 00:08:43,520 --> 00:08:48,280 starting with lithium. Where does it come from and what 143 00:08:48,280 --> 00:08:52,120 processes concentrate it and bring it to the surface so? 144 00:08:52,120 --> 00:08:56,480 Lithium supply is dominated by production from 2 very different 145 00:08:56,480 --> 00:09:00,760 types of lithium deposits. One we refer to as lithium 146 00:09:00,760 --> 00:09:03,760 pigmatites and the second lithium bronze. 147 00:09:04,040 --> 00:09:07,800 I'll talk about lithium pigmatites first, where lithium 148 00:09:07,800 --> 00:09:12,320 occurs as a mineral called spodumene, and spodumene is a 149 00:09:12,320 --> 00:09:16,280 mineral that contains lithium and aluminum and silicon bonded 150 00:09:16,280 --> 00:09:20,280 to oxygen. Now pegmatites are igneous rocks 151 00:09:20,600 --> 00:09:24,480 of generally granitic composition, and in some of the 152 00:09:24,480 --> 00:09:28,240 pegmatites that we mine, lithium from spodumene crystals can be 153 00:09:28,240 --> 00:09:31,200 on the order of a meter in length or greater. 154 00:09:32,280 --> 00:09:37,240 Pegmatites form at the margins of granitic magma intrusions, 155 00:09:37,640 --> 00:09:41,360 and they appear to be the very last stages of the magma to 156 00:09:41,360 --> 00:09:44,720 crystallize. There's one group of pegmatites 157 00:09:44,720 --> 00:09:47,400 that are really important for lithium and they're called the 158 00:09:47,400 --> 00:09:50,320 Lithium cesium Tantalum group pegmatite. 159 00:09:50,800 --> 00:09:55,960 They represent about 25% of all of the known lithium resources. 160 00:09:56,640 --> 00:10:00,800 Lithium rich pegmatites form from highly fractionated water 161 00:10:00,800 --> 00:10:05,600 rich silicate melts and it's thought that multiple stages of 162 00:10:05,600 --> 00:10:09,560 melting of Earth's crust are required to concentrate lithium 163 00:10:09,560 --> 00:10:13,200 to high enough concentrations for the mineral spodumene to 164 00:10:13,200 --> 00:10:16,960 crystallize during sort of the last gasp of the magma. 165 00:10:16,960 --> 00:10:22,400 In these systems, economic pegmatites contain as much as 2% 166 00:10:22,400 --> 00:10:26,520 lithium and we find them around the world, Australia, China, 167 00:10:26,520 --> 00:10:30,920 Zimbabwe, Portugal, Brazil, Canada, Russia, the United 168 00:10:30,920 --> 00:10:34,520 States and other countries. The largest deposits in the 169 00:10:34,520 --> 00:10:38,840 world are found in Australia. In fact, Australia have five of 170 00:10:38,840 --> 00:10:42,960 the top ten largest producing lithium mines in the world and 171 00:10:42,960 --> 00:10:46,960 all five of these are lithium pegmatites in the greenstone 172 00:10:46,960 --> 00:10:50,880 belts of WA. The second type of lithium 173 00:10:50,880 --> 00:10:55,120 deposit that's important are lithium brines and you can think 174 00:10:55,120 --> 00:11:00,520 of lithium brine deposits as really large volumes of salty 175 00:11:00,520 --> 00:11:05,280 groundwater enriched in lithium. And we find lithium brine 176 00:11:05,280 --> 00:11:11,560 deposits in dry inland lake beds known as playas or solars, and 177 00:11:11,560 --> 00:11:14,480 these formed by the evaporation of freshwater. 178 00:11:14,800 --> 00:11:20,480 So when freshwater in solars and playas evaporates, it tends to 179 00:11:20,480 --> 00:11:25,720 add elements such as lithium to the groundwaters, which is 180 00:11:25,720 --> 00:11:29,120 opposite of what we find in the oceans where the evaporation of 181 00:11:29,120 --> 00:11:32,480 ocean water doesn't lead to the formation of lithium rich 182 00:11:32,480 --> 00:11:35,600 brines. The most economically important 183 00:11:35,600 --> 00:11:39,560 lithium brines in the world form in arid regions in what we call 184 00:11:39,560 --> 00:11:43,680 the Lithium Triangle in Bolivia, Chile and Argentina. 185 00:11:44,120 --> 00:11:46,680 These lithium reserves are just enormous. 186 00:11:46,680 --> 00:11:49,840 They're about 10 times greater than all of the lithium 187 00:11:49,840 --> 00:11:53,840 pigmatites in Australia. There are other lithium brines 188 00:11:53,840 --> 00:11:56,440 around the world. There are lithium brines in the 189 00:11:56,440 --> 00:12:00,160 Clayton Valley in Nevada in the western United States, the 190 00:12:00,160 --> 00:12:05,120 Salton Sea in California, Zabui Lake on the Tibetan Plateau in 191 00:12:05,120 --> 00:12:07,280 China. And then there are some new 192 00:12:07,280 --> 00:12:09,600 lithium resources that are being developed. 193 00:12:09,960 --> 00:12:14,080 Among them there are some clay hosted lithium deposits in 194 00:12:14,080 --> 00:12:18,200 Nevada, where lithium is hosted in sediments in ryolitic 195 00:12:18,200 --> 00:12:21,480 calderas. And after these calderas erupt, 196 00:12:21,800 --> 00:12:25,320 all of the ryolitic material inside the caldera gets 197 00:12:25,320 --> 00:12:30,120 weathered by rain that falls on and percolates down through 198 00:12:30,120 --> 00:12:32,600 these rocks to convert them into clay. 199 00:12:33,280 --> 00:12:36,800 There's a lot of research being done now to try and extract 200 00:12:36,800 --> 00:12:41,680 lithium from geothermal waters and oilfield brines, and this is 201 00:12:41,680 --> 00:12:44,560 commonly talked about in the news as direct lithium 202 00:12:44,560 --> 00:12:48,240 extraction. So pumping groundwater up, 203 00:12:48,360 --> 00:12:51,040 pulling out the lithium, and then pumping the groundwater 204 00:12:51,040 --> 00:12:54,240 down. So there's effectively no impact 205 00:12:54,240 --> 00:12:57,160 on the local environment other than to remove the lithium. 206 00:12:57,800 --> 00:13:02,560 In these lithium brines, what's the origin of the lithium in the 207 00:13:02,560 --> 00:13:05,600 1st place? Is it leached out of deposits 208 00:13:05,600 --> 00:13:09,080 that contain spodumene? That lithium is dissolved from 209 00:13:09,080 --> 00:13:13,000 all of the rock formations that host the salty groundwater. 210 00:13:13,360 --> 00:13:17,480 So on geologic time scales, salty groundwater is really 211 00:13:17,480 --> 00:13:20,680 effective at dissolving minerals in the rocks through which it 212 00:13:20,680 --> 00:13:25,600 flows, and lithium is very soluble when there's chlorine in 213 00:13:25,600 --> 00:13:27,680 the water. And then the concentration 214 00:13:27,680 --> 00:13:30,480 happens through evaporation on the surface. 215 00:13:30,480 --> 00:13:32,720 Correct. In the Lithium Triangle in South 216 00:13:32,720 --> 00:13:35,680 America, the lithium brines. They're pumped to the surface 217 00:13:36,080 --> 00:13:40,760 and then put into pools, and as the water evaporates under the 218 00:13:40,760 --> 00:13:44,800 intense sunlight in the Atacama Desert, that concentrates 219 00:13:44,800 --> 00:13:49,440 lithium, which will precipitate out of the brine as either a 220 00:13:49,440 --> 00:13:52,560 lithium hydroxide or a lithium carbonate mineral. 221 00:13:52,920 --> 00:13:56,920 I remember when I flew up from Santiago to Kalama in the north 222 00:13:56,920 --> 00:14:01,880 of Chile and I saw out the window these huge green ponds. 223 00:14:02,160 --> 00:14:04,920 I suppose these must have been lithium evaporation ponds. 224 00:14:05,000 --> 00:14:07,680 Absolutely, Yeah, you see those. That's a great flight. 225 00:14:07,840 --> 00:14:11,840 One of the concerns about the method of evaporation to 226 00:14:11,840 --> 00:14:16,680 concentrate lithium in that area is the amount of groundwater 227 00:14:16,680 --> 00:14:19,560 that is effectively then lost to the atmosphere through 228 00:14:19,560 --> 00:14:22,880 evaporation. And this has stimulated a lot of 229 00:14:22,880 --> 00:14:25,680 research and development in direct lithium extraction. 230 00:14:26,040 --> 00:14:30,720 So if we can imagine putting pipes down into this lithium 231 00:14:30,720 --> 00:14:34,640 rich groundwater and piping that water to the surface and then 232 00:14:34,640 --> 00:14:38,520 just selectively pulling the lithium out, we can pump that 233 00:14:38,520 --> 00:14:44,840 water back down underground and that then reduces the impact on 234 00:14:44,840 --> 00:14:48,480 the environment. OK, let's move on to copper. 235 00:14:49,360 --> 00:14:53,520 We've been mining copper for a very long time, so presumably 236 00:14:53,520 --> 00:14:55,920 the sources of copper are pretty well established. 237 00:14:56,400 --> 00:14:59,520 So there are several important types of copper deposits. 238 00:14:59,840 --> 00:15:03,080 The most important are what we call porphyry copper deposits 239 00:15:03,080 --> 00:15:07,480 that supply about 60% of the world's copper, followed by 240 00:15:07,480 --> 00:15:11,120 sediment hosted copper deposits. And then there are three other 241 00:15:11,120 --> 00:15:15,520 deposits, magmatic sulfide deposits, iron oxide, copper 242 00:15:15,520 --> 00:15:19,720 gold deposits and volcanogenic massive sulfide deposits. 243 00:15:19,960 --> 00:15:22,480 But I'll start by describing porphyry deposits. 244 00:15:22,800 --> 00:15:27,520 So the word porphyry refers to the porphyritic texture of 245 00:15:27,520 --> 00:15:30,320 igneous rocks that host the copper minerals in these 246 00:15:30,320 --> 00:15:33,320 deposits. And a porphyritic rock is a 247 00:15:33,320 --> 00:15:37,680 mixture of large crystals which we call phenocrysts, and small 248 00:15:37,680 --> 00:15:39,720 crystals that we call ground mass. 249 00:15:39,720 --> 00:15:43,160 Is the copper in the big crystals or within the matrix? 250 00:15:43,520 --> 00:15:48,960 In the matrix, in very thin veins within the matrix, the 251 00:15:48,960 --> 00:15:53,280 most important porphyry copper deposits are found at convergent 252 00:15:53,280 --> 00:15:57,320 tectonic margins above active subduction zones. 253 00:15:57,640 --> 00:16:02,240 So places such as the Andes in South America, or the very 254 00:16:02,240 --> 00:16:06,160 volcanically active areas of Indonesia and the Philippines, 255 00:16:06,600 --> 00:16:11,680 Alaska and the western United States, places like Arizona and 256 00:16:11,680 --> 00:16:17,720 Utah, porphyry deposits form from magmas in volcanic systems. 257 00:16:18,000 --> 00:16:22,760 Magmas are composed of a liquid which is a silicate rich melt, 258 00:16:23,360 --> 00:16:26,920 and the silicate rich melt contains copper and every other 259 00:16:26,920 --> 00:16:31,120 metal and element in the periodic table, plus solid 260 00:16:31,120 --> 00:16:36,320 minerals inside the magma and then gases, carbon dioxide and 261 00:16:36,320 --> 00:16:38,440 water that are dissolved in the melt. 262 00:16:38,840 --> 00:16:42,640 And as a magma is moving from deep within Earth's crust 263 00:16:42,640 --> 00:16:46,880 towards the surface, all of these gases are dissolved in the 264 00:16:46,880 --> 00:16:52,080 melt in subduction zones. So imagine the Andes of South 265 00:16:52,080 --> 00:16:55,600 America where we've got the Pacific Ocean plate moving from 266 00:16:55,600 --> 00:16:59,640 West to east and the very large South American plate moving from 267 00:16:59,640 --> 00:17:03,280 east to West. That compression can cause the 268 00:17:03,280 --> 00:17:08,079 crust in South America to get really thick, 30405060 269 00:17:08,079 --> 00:17:12,520 kilometers thick. And in really thick crust in 270 00:17:12,520 --> 00:17:16,920 seduction zone environments, the magmas get progressively more 271 00:17:16,920 --> 00:17:20,720 silica rich and they get more water rich. 272 00:17:21,040 --> 00:17:24,960 We refer to these types of magmas as granitic, the same 273 00:17:24,960 --> 00:17:28,040 types of granites I mentioned earlier that evolved lithium 274 00:17:28,040 --> 00:17:30,960 pigmatites. Now what's important about the 275 00:17:30,960 --> 00:17:36,120 granitic magmas is they have a very high silica content, which 276 00:17:36,120 --> 00:17:38,600 increases the viscosity of the magma. 277 00:17:38,600 --> 00:17:42,240 So think about these magmas as you know, something like frozen 278 00:17:42,240 --> 00:17:44,720 peanut butter. It's really hard for them to 279 00:17:44,720 --> 00:17:47,800 move. But eventually, when these 280 00:17:47,800 --> 00:17:51,840 magmas get close to the surface of the Earth, the melt part of 281 00:17:51,840 --> 00:17:56,480 the magma can no longer keep water dissolved in the melt, and 282 00:17:56,480 --> 00:18:00,680 so that water dissolves from the melt to form bubbles. 283 00:18:01,080 --> 00:18:04,400 And you can picture these bubbles as bubbles in a glass of 284 00:18:04,400 --> 00:18:08,000 champagne. These bubbles are dominantly 285 00:18:08,000 --> 00:18:11,720 water. But elements like copper and 286 00:18:11,720 --> 00:18:17,040 sulfur and chlorine also really prefer to be in these bubbles 287 00:18:17,240 --> 00:18:20,280 versus the melt. So copper and sulfur will 288 00:18:20,280 --> 00:18:24,040 partition or transfer from the melt into the bubbles. 289 00:18:24,960 --> 00:18:29,320 Now in the magma, these bubbles that contain copper and sulphur, 290 00:18:29,600 --> 00:18:34,360 they're really buoyant and they ascend towards the surface of 291 00:18:34,360 --> 00:18:36,880 the magma. And when they get to the surface 292 00:18:36,880 --> 00:18:40,680 of the magma, unlike our glass of champagne where the bubbles 293 00:18:40,680 --> 00:18:45,200 can just pop, in a magma, the bubbles will pond. 294 00:18:45,560 --> 00:18:50,400 And at the top of the magma chamber we get this coalescence 295 00:18:50,400 --> 00:18:57,800 of trillions of bubbles that form this layer of very copper 296 00:18:57,800 --> 00:19:04,480 rich, sulphur rich liquid. And eventually those bubbles can 297 00:19:04,480 --> 00:19:08,640 exert a lot of pressure outward on the magma and they can cause 298 00:19:08,640 --> 00:19:11,400 an eruption. And this is the eruption that 299 00:19:11,400 --> 00:19:14,040 you see if you pop the cork on champagne. 300 00:19:14,400 --> 00:19:17,880 And all of that gas in the liquid immediately wants to get 301 00:19:17,880 --> 00:19:21,600 out to the atmosphere. The same thing happens to form 302 00:19:21,600 --> 00:19:25,680 porphy deposits where these copper and sulfur rich bubbles 303 00:19:25,840 --> 00:19:29,200 erupt from the magma. But they're erupting at a 304 00:19:29,200 --> 00:19:32,920 kilometer, 2 kilometers, 3 kilometers below the surface. 305 00:19:33,360 --> 00:19:37,440 And as soon as they erupt, they wiggle their way towards the 306 00:19:37,440 --> 00:19:41,000 surface, through all of the rock above the magma chamber. 307 00:19:41,360 --> 00:19:45,240 They're cooling off, they're decompressing, and they're also 308 00:19:45,240 --> 00:19:48,120 reacting with all of the rocks through which they flow. 309 00:19:48,520 --> 00:19:53,880 And this results in the almost instantaneous precipitation of 310 00:19:53,880 --> 00:19:55,840 minerals that are enriched in copper. 311 00:19:56,200 --> 00:19:59,320 And all of this happens in a really small volume of the 312 00:19:59,320 --> 00:20:03,560 Earth's crust and results in the formation of porphyry copper 313 00:20:03,560 --> 00:20:07,240 deposits. OK, let's move on and talk about 314 00:20:07,240 --> 00:20:10,040 nickel. What's its geological origin and 315 00:20:10,040 --> 00:20:14,680 the context in which we find it? We get nickel from 2 main types 316 00:20:14,680 --> 00:20:18,240 of deposit laterites and sulfide deposits. 317 00:20:18,920 --> 00:20:23,400 Laterites today supply about half of the world's nickel, and 318 00:20:23,400 --> 00:20:26,760 they're forecasted to supply about 80% of nickel within the 319 00:20:26,760 --> 00:20:30,080 next decade. Most of our nickel from 320 00:20:30,080 --> 00:20:33,480 laterites comes from Indonesia, New Caledonia and the 321 00:20:33,480 --> 00:20:36,680 Philippines. These are areas that contain 322 00:20:36,680 --> 00:20:41,560 huge amounts of ultra mafic rocks like perititite and donite 323 00:20:41,560 --> 00:20:45,160 that are really rich in magnesium in the mineral 324 00:20:45,160 --> 00:20:49,040 olivine. These ultra mafic rocks can 325 00:20:49,040 --> 00:20:52,240 contain as much as several thousand parts per million 326 00:20:52,240 --> 00:20:57,080 nickel in olivine where nickel substitutes for magnesium. 327 00:20:57,760 --> 00:21:01,560 Olivine in these rocks on the surface of the earth is really 328 00:21:01,560 --> 00:21:05,800 thermodynamically unhappy. As warm rainwater percolates 329 00:21:05,800 --> 00:21:09,520 down through the ultra mafic rock, it reacts with and breaks 330 00:21:09,520 --> 00:21:14,760 down olivine and this releases the magnesium and the nickel and 331 00:21:14,760 --> 00:21:17,400 the iron in the olivine to the groundwater. 332 00:21:17,840 --> 00:21:21,400 And as soon as this happens, if the groundwater contains 333 00:21:21,400 --> 00:21:25,920 dissolved oxygen, iron immediately precipitates as an 334 00:21:25,920 --> 00:21:31,680 iron oxide that adsorbs nickel from the water and it results in 335 00:21:31,680 --> 00:21:37,000 the concentration of nickel in very thin zones within these 336 00:21:37,000 --> 00:21:41,360 ultra mafic rocks. If the groundwater is reduced, 337 00:21:41,640 --> 00:21:45,560 then nickel can remain dissolved in the groundwater and it will 338 00:21:45,560 --> 00:21:49,680 percolate down to the bottom of the weathered zone where it can 339 00:21:49,680 --> 00:21:53,680 precipitate as minerals like garnierite, which is a really 340 00:21:53,680 --> 00:21:59,040 complex nickel silicate mineral and again precipitates in a very 341 00:21:59,400 --> 00:22:02,840 thin layer from which we can mine the nickel. 342 00:22:03,280 --> 00:22:06,400 OK. We hear a lot about cobalt 343 00:22:06,400 --> 00:22:10,080 because it mainly comes from the Democratic Republic of Congo, 344 00:22:10,520 --> 00:22:14,080 which is problematic because of child labor and other issues. 345 00:22:14,600 --> 00:22:17,600 What is the geological origin of the cobalt? 346 00:22:18,360 --> 00:22:23,200 So in the Democratic Republic of Congo and other areas, cobalt is 347 00:22:23,200 --> 00:22:27,720 associated with copper and these deposits are referred to as 348 00:22:27,720 --> 00:22:30,360 sediment hosted copper, cobalt deposits. 349 00:22:30,880 --> 00:22:34,240 And they contain copper and cobalt in the form of copper 350 00:22:34,240 --> 00:22:38,800 oxides and cobalt oxides and copper and cobalt sulfide 351 00:22:38,800 --> 00:22:42,000 minerals. And they're found concentrated 352 00:22:42,000 --> 00:22:46,720 in layers in sedimentary rocks. We find them in the African 353 00:22:46,720 --> 00:22:50,720 Copper Belt, which extends from Angola across the Democratic 354 00:22:50,720 --> 00:22:55,520 Republic of the Congo into Zambia, and also in the Cooper 355 00:22:55,520 --> 00:22:59,000 Schieffer in Germany and Poland. In fact, the word Cooper 356 00:22:59,000 --> 00:23:02,400 Schieffer means copper shale and people have been mining copper 357 00:23:02,400 --> 00:23:04,640 in this area for at least 1000 years. 358 00:23:05,040 --> 00:23:08,680 Do we know what the geological origin of that very large 359 00:23:08,720 --> 00:23:13,520 African copper belt is and how it came to be enriched in copper 360 00:23:13,600 --> 00:23:18,360 and other metals? So that area in the geologic 361 00:23:18,360 --> 00:23:24,520 past contained really expansive shallow continental and marine 362 00:23:24,520 --> 00:23:28,240 sedimentary basins, if we think about the Gulf of Mexico or the 363 00:23:28,240 --> 00:23:30,640 Mediterranean Sea as a modern analog. 364 00:23:31,240 --> 00:23:36,480 So we've got the deposition of muds and silts and sands to form 365 00:23:36,520 --> 00:23:40,520 really thick sequences of mud stones and sand stones and silt 366 00:23:40,520 --> 00:23:43,240 stones. And it's within those sand 367 00:23:43,240 --> 00:23:47,240 stones that the salty groundwater is first birthed, 368 00:23:47,360 --> 00:23:51,840 probably from the dissolution of evaporites after all of the 369 00:23:51,840 --> 00:23:55,920 water has evaporated and precipitated salts at the bottom 370 00:23:55,920 --> 00:23:59,360 of these basins. So the general model for how 371 00:23:59,360 --> 00:24:03,760 these deposits form in the African copper belt involves the 372 00:24:03,760 --> 00:24:08,880 movement of oxidized copper bearing salty hydrothermal 373 00:24:08,880 --> 00:24:11,920 fluids. So think salty groundwater 374 00:24:11,920 --> 00:24:15,400 similar to what we talked about for lithium, but in this case 375 00:24:15,400 --> 00:24:20,000 the salty groundwater is able to dissolve high concentrations of 376 00:24:20,000 --> 00:24:23,680 copper and cobalt. And as long as the groundwater 377 00:24:23,680 --> 00:24:28,000 is percolating through rocks that are oxidized, so think 378 00:24:28,000 --> 00:24:32,560 oxidized sandstones or red beds, then the copper and cobalt are 379 00:24:32,560 --> 00:24:36,480 perfectly happy to be dissolved in that salty groundwater. 380 00:24:37,600 --> 00:24:42,000 But if that salty groundwater encounters rocks that are very 381 00:24:42,000 --> 00:24:48,680 reduced, so rocks such as shales or mud stones, silt stones that 382 00:24:48,680 --> 00:24:53,360 contain high concentrations of carbon and sulphur, then the 383 00:24:53,360 --> 00:24:58,120 sulphur in these reduced rocks will reduce the cobalt and 384 00:24:58,120 --> 00:25:01,320 copper groundwater flowing through the oxidized rocks. 385 00:25:01,720 --> 00:25:06,200 And at the interface between the reduced and oxidized rocks, the 386 00:25:06,200 --> 00:25:10,040 sulphur in the reduced rocks will react with copper and 387 00:25:10,040 --> 00:25:13,880 cobalt in the oxidized groundwater to precipitate 388 00:25:13,880 --> 00:25:16,880 sulphides that are enriched in copper and cobalt. 389 00:25:17,760 --> 00:25:23,400 And this happens in relatively localized volumes of sheet like 390 00:25:23,400 --> 00:25:28,040 or lens like ore bodies that forms very high concentrations 391 00:25:28,040 --> 00:25:33,640 of copper and cobalt in small volumes of rock in the African 392 00:25:33,640 --> 00:25:39,080 copper belt over geologic time, the upper few 10s of meters to 393 00:25:39,080 --> 00:25:41,440 maybe 100 meters of these deposits. 394 00:25:41,800 --> 00:25:46,120 As rainwater has percolated from the surface down through these 395 00:25:46,120 --> 00:25:50,640 rocks, it oxidized the cobalt sulphide minerals to cobalt 396 00:25:50,640 --> 00:25:54,320 oxide minerals. And that makes the cobalt much 397 00:25:54,320 --> 00:25:58,600 more attractive economically to mine because it's easier to 398 00:25:58,600 --> 00:26:02,000 process and produce cobalt from an oxide mineral than it is a 399 00:26:02,000 --> 00:26:06,120 sulphide mineral. The 2nd place we get cobalt are 400 00:26:06,120 --> 00:26:08,880 from the nickel rich laterites that we talked about. 401 00:26:09,360 --> 00:26:13,400 So these nickel rich laterites also contain relatively high 402 00:26:13,400 --> 00:26:17,480 concentration of cobalt on the order of a few 100 to a few 403 00:26:17,480 --> 00:26:22,800 thousand parts per million cobalt and cobalt is produced as 404 00:26:22,800 --> 00:26:25,880 a byproduct of nickel mining from these regions. 405 00:26:26,440 --> 00:26:29,920 The last critical metal is manganese. 406 00:26:30,320 --> 00:26:33,000 Can you tell us about the origin of the manganese deposits? 407 00:26:33,640 --> 00:26:38,040 Most of our manganese comes from sedimentary deposits that 408 00:26:38,040 --> 00:26:42,440 precipitated from sea water during sea water evaporation. 409 00:26:42,720 --> 00:26:46,200 So again, thinking about modern day basins like the 410 00:26:46,200 --> 00:26:50,000 Mediterranean Sea, if we imagine the Mediterranean Sea 411 00:26:50,000 --> 00:26:54,000 evaporating on geologic time scales under the right 412 00:26:54,000 --> 00:26:58,240 conditions within the water, manganese will precipitate out 413 00:26:58,240 --> 00:27:00,720 of that water to form manganese minerals. 414 00:27:01,480 --> 00:27:05,080 These sedimentary manganese deposits supply most of the 415 00:27:05,080 --> 00:27:08,640 world production and they consist of layers of manganese 416 00:27:08,640 --> 00:27:12,920 carbonates and oxides that were precipitated as these chemical 417 00:27:12,920 --> 00:27:16,800 sediments. We find manganese deposits on 418 00:27:16,800 --> 00:27:21,600 Earth that formed both before the great oxidation event, so 419 00:27:21,720 --> 00:27:25,800 about 2 1/2 billion years ago when the Earth's atmosphere went 420 00:27:25,800 --> 00:27:28,760 from having very low concentration of oxygen to 421 00:27:28,760 --> 00:27:31,920 gradually the much higher concentration of oxygen we have 422 00:27:31,920 --> 00:27:34,960 today. And manganese deposits that 423 00:27:34,960 --> 00:27:38,160 formed before the great oxidation event, they're 424 00:27:38,160 --> 00:27:41,080 dominated by manganese 2 plus minerals. 425 00:27:41,280 --> 00:27:45,280 So manganese bearing carbonates and manganese deposits that 426 00:27:45,280 --> 00:27:49,560 formed after the great oxidation event tend to be dominated by 427 00:27:49,560 --> 00:27:54,760 manganese 3 plus and four plus in oxides and hydroxides. 428 00:27:55,160 --> 00:27:59,280 And we very commonly find these oxidized manganese deposits 429 00:27:59,280 --> 00:28:03,480 associated with banded iron formations where iron in the 430 00:28:03,480 --> 00:28:09,200 world's oceans precipitated as iron 2 plus and three plus in 431 00:28:09,200 --> 00:28:11,360 minerals like hematite and magnetite. 432 00:28:12,200 --> 00:28:16,080 So it sounds like when you think about it globally, that we have 433 00:28:16,160 --> 00:28:20,240 a pretty abundant supply of all these critical metals, albeit 434 00:28:20,320 --> 00:28:23,920 some of them beset by geopolitical problems, but it 435 00:28:23,920 --> 00:28:26,880 doesn't sound like we'll be running out of any of them soon. 436 00:28:27,480 --> 00:28:32,760 No, we have more than enough of each of these metals to build 437 00:28:32,760 --> 00:28:36,360 the batteries that the energy transition requires. 438 00:28:36,720 --> 00:28:40,240 It's the batteries for the energy transition from 439 00:28:40,240 --> 00:28:43,360 combustion engines to battery electric vehicles. 440 00:28:43,760 --> 00:28:48,280 It's also the energy transition for a majority of people around 441 00:28:48,280 --> 00:28:53,200 the world to transition from very low energy to what we think 442 00:28:53,200 --> 00:28:57,320 of as normal amounts of energy consumption in the European 443 00:28:57,320 --> 00:28:59,840 Union, the United States and other countries. 444 00:29:00,600 --> 00:29:04,600 So we know we have enough of these metals around the world. 445 00:29:04,880 --> 00:29:09,000 The challenge is the rate at which mining companies can 446 00:29:09,000 --> 00:29:12,480 extract them to make them available for manufacturing the 447 00:29:12,480 --> 00:29:14,200 batteries and other technologies. 448 00:29:15,160 --> 00:29:18,960 All the five metals we've talked about likely to remain critical 449 00:29:18,960 --> 00:29:23,360 for batteries, or do you think new technologies will reduce our 450 00:29:23,360 --> 00:29:26,240 need for them or create a demand for other elements? 451 00:29:26,520 --> 00:29:30,120 I think the general consensus is that these metals will be the 452 00:29:30,120 --> 00:29:32,840 most important for electrification and energy 453 00:29:32,840 --> 00:29:35,160 storage for at least the next few decades. 454 00:29:35,800 --> 00:29:40,000 Research and development now is focused on increasing energy 455 00:29:40,000 --> 00:29:43,280 density, which is really important for battery electric 456 00:29:43,280 --> 00:29:46,320 vehicles. Increasing power density. 457 00:29:46,320 --> 00:29:51,880 So how much energy can a battery provide per instant of time? 458 00:29:52,760 --> 00:29:57,080 Increasing the charging rate so allowing batteries to be 459 00:29:57,080 --> 00:29:59,840 recharged much faster than they are today. 460 00:30:00,280 --> 00:30:04,160 Lots of research and development on increasing battery lifespan 461 00:30:04,440 --> 00:30:07,040 and increasing the cycle life of a battery. 462 00:30:07,040 --> 00:30:12,360 So when we buy a phone today, it's designed for us to charge 463 00:30:12,360 --> 00:30:16,400 and discharge it somewhere on the order of 506 hundred times. 464 00:30:16,960 --> 00:30:19,760 Well, why can't we have phones where we can discharge and 465 00:30:19,760 --> 00:30:23,120 recharge the battery 1000 * 5000 times? 466 00:30:23,840 --> 00:30:27,280 Also trying to continue to reduce battery costs. 467 00:30:27,280 --> 00:30:31,360 Battery costs have dropped 99% in the last 30 years. 468 00:30:31,880 --> 00:30:35,600 But can we continue to make batteries cheaper while also 469 00:30:35,600 --> 00:30:37,600 making them better and making them safer? 470 00:30:38,320 --> 00:30:42,120 There's a lot of research being done on solid-state batteries. 471 00:30:42,360 --> 00:30:46,400 So instead of having a liquid electrolyte, having a solid 472 00:30:46,400 --> 00:30:50,680 electrolyte, they could be a ceramic and also replacing the 473 00:30:50,680 --> 00:30:55,240 graphite anode with other anodes, graphite combined with 474 00:30:55,240 --> 00:31:00,400 silicon, possibly silicon anodes, and even using lithium 475 00:31:00,400 --> 00:31:03,440 metal as an anode. So I think over the next few 476 00:31:03,440 --> 00:31:06,960 decades, the metals that we've talked about here will continue 477 00:31:06,960 --> 00:31:10,280 to dominate batteries. But over the next few decades, 478 00:31:10,280 --> 00:31:13,440 we'll see the composition of the cathodes will change. 479 00:31:13,720 --> 00:31:16,400 We'll see. All of the positive factors of 480 00:31:16,400 --> 00:31:18,400 batteries just continue to get better. 481 00:31:19,160 --> 00:31:22,120 So what are you working on at the moment in your research? 482 00:31:22,640 --> 00:31:26,800 So among all the metals in the periodic table, my favorite has 483 00:31:26,800 --> 00:31:30,120 always been copper. Copper is the metal that is most 484 00:31:30,120 --> 00:31:34,520 fundamental to all technologies. So we can play around with the 485 00:31:34,520 --> 00:31:37,080 ratio of nickel to cobalt in batteries. 486 00:31:37,320 --> 00:31:41,000 We can reduce just a bit the amount of copper that we need, 487 00:31:41,400 --> 00:31:44,920 but we need copper to generate electricity, to move 488 00:31:44,920 --> 00:31:47,280 electricity, to store electricity. 489 00:31:47,720 --> 00:31:52,000 And the amount of copper that society will need over the next 490 00:31:52,000 --> 00:31:56,960 few decades for the energy transition is more than the 491 00:31:56,960 --> 00:32:01,640 amount of copper we have mined since the end of the Stone Age. 492 00:32:02,160 --> 00:32:04,680 So where is all this copper going to come from? 493 00:32:05,200 --> 00:32:09,120 Mining companies are discovering less and less new copper. 494 00:32:09,440 --> 00:32:13,160 So I focus on trying to understand how do we search for 495 00:32:13,160 --> 00:32:15,160 and discover new copper deposits? 496 00:32:15,440 --> 00:32:18,840 And how do you do that? So with a couple of partners, we 497 00:32:18,840 --> 00:32:23,080 looked at waters that move through natural copper deposits, 498 00:32:23,360 --> 00:32:28,440 groundwater and surface water, and we started analyzing the 499 00:32:28,440 --> 00:32:32,760 composition of waters from around the areas of known copper 500 00:32:32,760 --> 00:32:36,680 deposits all over the world. And when we analyze water 501 00:32:36,680 --> 00:32:40,200 samples, we measure everything from lithium to uranium, so 502 00:32:40,200 --> 00:32:45,200 every metal in the periodic table and we measure all of the 503 00:32:45,200 --> 00:32:49,920 metal abundances, plus we measure the isotopic abundances. 504 00:32:50,160 --> 00:32:54,480 And then we use those data to figure out what is the metal 505 00:32:54,480 --> 00:32:58,280 isotopic signature of groundwater and surface water 506 00:32:58,680 --> 00:33:03,240 that is a fingerprint for that water having interacted with 507 00:33:03,240 --> 00:33:05,280 copper minerals in the subsurface. 508 00:33:05,640 --> 00:33:09,040 And we figured out what that fingerprint is. 509 00:33:09,400 --> 00:33:14,040 So we're applying our technology to help mining companies screen 510 00:33:14,040 --> 00:33:17,680 areas around the world for the presence or absence of copper 511 00:33:17,680 --> 00:33:20,560 minerals. So all we need is a few 100 512 00:33:20,560 --> 00:33:23,560 milliliters of water. And that water can come from any 513 00:33:23,560 --> 00:33:27,360 natural source, from a spring, from a seep, from a small lake 514 00:33:27,360 --> 00:33:29,840 or pond. We've even sampled water from 515 00:33:29,840 --> 00:33:34,040 the Zambezi River, and we can tell you whether or not it 516 00:33:34,040 --> 00:33:36,320 fingerprints the presence of copper minerals. 517 00:33:37,480 --> 00:33:40,440 Adam Simon, thank you very much. Well, thank you, Oliver. 518 00:33:40,440 --> 00:33:43,000 I really appreciated this opportunity to chat with you 519 00:33:43,000 --> 00:33:45,600 about batteries and the metals that we need to make them. 520 00:33:46,960 --> 00:33:49,640 To see pictures and illustrations that support this 521 00:33:49,640 --> 00:33:55,200 podcast, go to geologybytes.com, where you'll also find 522 00:33:55,200 --> 00:33:58,680 transcripts and a subject matter index of all the episodes. 523 00:33:59,200 --> 00:34:02,560 There you can also give me feedback which I welcome, as 524 00:34:02,560 --> 00:34:05,560 well as sign up to get my emails about new episodes.