LTO- An alternative battery chemistry

The automobile industry has evolved with EV segments, providing green solutions for sustainable mobility. Batteries are the backbone of the electric vehicle, and the car’s range depends on the battery’s composition, i.e., the higher the battery capacity, the higher the range. The commonly used rechargeable batteries for electric mobility with durability are lithium-Ion, Nickel-metal, and Lead-acid batteries.     

Lead-acid batteries are an old technology that is reliable, recyclable and has a short life cycle. Nickel-metal batteries are used in computers to petrol hybrid vehicles and offer specific power capabilities with a safe and excellent life cycle. Regenerative braking and speed of the car offer in-car charging. 

Li-ion batteries are used in almost every electronic from a cell phone to an electric vehicle due to higher energy density, i.e. high power-to-weight ratio, better performance at higher temperatures, high energy efficiency and low self-discharge. These batteries are light, robust and durable in the long run. Today all-electric vehicles and PHEVs use lithium-ion batteries. Their chemistry often varies from that of consumer electronics batteries. 

There are various Li-ion batteries; Lithium-iron phosphate, Lithium Titanate, Lithium Nickel manganese cobalt, Lithium manganese oxide, and lithium nickel cobalt-aluminium oxide.  

Producing LTO involves a complicated synthesis of Lithium titanium oxide, the chemical needed for its anode, thus making the battery costly. Researchers at the International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI) are researching on a simple process for the synthesis of lithium titanium oxide (LTO) which is a anode material required for high power batteries.  

Lithium titanium oxide (LTO) is emerging as a promising anode material for high-power Lithium-Ion-batteries (LIBs) owing to its abundance, thermal stability, high cycle life of more than 20000 cycles and safety benefits . It has negligible volume change during charging and discharging, which ensures an extremely long cycle life and can work under harsh ambient temperatures exhibiting recharge efficiency, which makes it suitable for Indian climatic conditions. Many techniques are accessible for the synthesis of LTO; they all involve highly complicated synthesis procedures, vast amounts of solvents, toxic chemicals and methods. To overcome the disadvantages in LTO, like poor electronic and ionic conductivity, require adding one more step to the synthesis process making it more complicated. 

To address the above challenges, the team focused on developing a simple, highly economical and energy-efficient manufacturing of LTO anode with stabilised electronic conductivity using TiO2 and Li2CO3 as precursors. The advantages of the high-energy milling method are low processing time, low contamination, and high energy input.   

Recycling Li-ion batteries is a widespread battery recycling technique that prevents hazardous materials from entering the waste system. The material recovery from recycling would reintroduce critical materials back into the supply chain and increase the domestic sources for such materials. Recycling processes vary with different methods of separation for material recovery:  

• Smelting: Smelting processes recover essential elements. These processes are operational on a large scale and can accept multiple kinds of batteries, including lithium-ion and nickel-metal hydride. The valuable metals are recovered and refined to make the product suitable for use. The other materials, including lithium, contained in the slag is now used as an additive in concrete industry.  
• Direct recovery: Some recycling processes directly recover battery-grade materials. Direct recovery is a low-temperature process with low energy requirements. Components are separated by a various physical and chemical processes. All active materials and metals can be recovered in this process.   

LTO batteries provide higher safety, operating temperatures and battery charging cycles in comparison with LFP. Energy density of LTO is lower than the LFP and hence there are different applications where LTO can be better suitable in cases like smaller energy needs which can afford more space and weight. The ability to fast charge with LTO is very high making it more suitable for scooter & motorcycles acting as an alternative battery chemistry solution.