A scientist at Busitema University has invented a battery derived from biomass-based materials and common salt. When Uganda starts making electric vehicles (EVs), this kind of battery is likely to make a big difference.
Currently, over 60% of the parts, including batteries, used by Kiira Motors (KMC) to manufacture cars and buses are imported from China. But Kampala-based lecturer and materials science and engineering expert Dr. Moses Kigozi says that with the new science of making lithium-ion and sodium-ion batteries, Uganda can stop buying them from other countries and start making them there.
“Because currently, we don’t have an existing plant for lithium-ion and sodium-ion batteries.” “I convert the locally available biomass, like coffee husks, maize cobs, and rice husks, into graphite, which can be used as the anode material or the negative part of the battery,” said Dr. Kigozi, who holds a Ph.D. in energy storage from India.
He says he uses the common salts from around Lake Katwe to get lithium-ion and sodium-ion to make the positive electrodes needed to combine a cell. The cells that Kigozi has are able to power cellphones and laptops, and if combined, they can power electric bikes.
Kigozi aims for massive production of eco-friendly batteries that can replace conventional activated carbon-based batteries made from fossil fuels. “Actually, I want to add value to materials that people discard as waste.” In one way, I’m trying to improve waste management because, in every acre of land where you harvest maize, you only target 20%, while 80% is waste. “So I use those materials to reduce the cost of the battery,” Kigozi told URN.
Lithium-ion batteries are expected to be the core of electric cars in the near future. So far, the power comes from the electric grids as well as household technology like smartphones and computers. Since electric cars are becoming more popular, the market for lithium-ion batteries is expected to reach $100 billion by 2025.
But around the world, there are groups advocating for a reduction in the dependence on lithium in the manufacture of batteries. The mining of lithium in countries like the DRC has been linked to environmental degradation as well as fueling conflict.
The main raw materials for lithium-ion, lithium, and cobalt come from the earth, but they take a lot of energy and water to extract. Lithium is difficult to extract as it’s typically found in trace amounts. Studies on several continents have confirmed that biomass from all kinds of waste can be carbonized and used in anodes for lithium or sodium ion batteries, cathodes in metal sulfur or metal oxygen batteries, or as conductive additives. Kigozi, in an interview, confirmed this.
A more recent study in Renewable and Sustainable Energy Reviews found that various types of biomass for lithium-sulfur batteries have grown to be competitors with Li-ion batteries. “Actually, technology has been in existence for years, and every year people try to improve the performance of the technology.” The technology that is currently available uses what we call “metal oxides” in the positive part of the battery. “I’m trying to reduce that metal and use carbon, which is locally available,” he explained.
So far, the dominant battery solution for renewable energy has been lithium-ion batteries (LIBs). Those batteries are prone to explosions and they don’t last long enough, and yet the world will need many more with bigger capacities that are friendly to the environment.
“My process for converting biomass into graphite has zero emissions.” I don’t produce any greenhouse gases like carbon dioxide, hydrogen, methane, and others. “Everything is captured to improve performance,” he said.
Kigozi’s kind of battery could attract interest from automakers like BMW and a group backed by German automobile giants including Daimler AG and Volkswagen AG that try to “green” the image of their electric cars by using batteries that are not made from metals like lithium-ion. Kigozi is one of the three Ugandans with extensive expertise in the fabrication of batteries. His two counterparts have already left Uganda for greener pastures.
“As far as I know, I’m the only one with a Ph.D. in energy storage.” I have tried to look around, and the only two friends with whom we were collaborating from other countries went for greener pastures. “One is working for Tesla, and the other is in the USA,” Kigozi revealed.
At Kigozi’s workstation are rechargeable coin cells powering digital devices like watches, lamps, calculators, toys, and car remote controls. He also has cells in pouches for charging mobile phones and makes hybrid supercapacitors, which are also key components needed in energy storage.
“In energy storage, we have capacitors and batteries.” Capacitors are good at giving high power, and batteries are good at giving high energy. “So we need a device that has both,” he explained. According to Kigozi, the tops of the capacitors were threaded at Makerere University’s engineering department, and the rest was assembled at Busitma University’s chemistry department. Kigozi told URN that he has not gone into mass production because he still lacks the machinery needed to do the assembly.
“I have the skills; I have the materials, but I’m lacking the machinery to go full commercial.” Otherwise, the market is readily available,” said Kigozi. There are about five new businesses in Uganda that can make rechargeable backup batteries for two-wheeled electric bikes, but none that make lithium-ion batteries.
Zembo Electric Motorcycles Co-Founder and Director, Daniel Dreher, said what Kigozi is doing is clearing the ground to launch Ugandans to make cells for electric vehicles. “Because of what is happening now, 90% of this market is Chinese.” Even in Germany, there are problems because car manufacturers like Volkswagen and Mercedes need to buy battery cells from China. “While in Uganda, we have a unique opportunity, even when landlocked, to put those processes into our country because we have the raw materials,” said Dreher.
At a global level, 2022 has seen a sharp rise in prices for lithium, which is a key mineral in the production of batteries for electric vehicles. Reports indicate that demand for lithium has outstripped supply, pushing prices up almost 500% in a year. The International Energy Agency (IEA) estimates that the world will require up to 10,000 GWh of electricity by 2040 to meet climate goals. This is fifty times the current global energy production.