Manganese Spinel Li ion Batteries are the dominant form of automotive Lithium ion battery, used in EVs, PHEVs and HEVs, ie LEAF, Volt, Hyundai/Kia hybrids etc. This is due to its desireable safety, cost and history.
The general principle is that by doping -> capacity is traded for robustness
ALL Commercial Manganese Spinel cathodes are doped, the reduction in capacity is about 20% below theoretical non doped manganese spinel. This is primarily achieved by slightly elevating the Li content, it also is achieved by adding small amount of Al, Mg, Ti, Ni etc.
The robustness is improved, which generally means temperature tolerance, cycle life, rate capacity and safety all improve at the same time, BUT energy capacity is reduced and the supply is more niche.
Blending a nickel based cathode (NCA, NMC) into a manganese spinel mix improves both robustness and energy capacity, but then adds further safety issues and higher costs. Nissan LEAF cells and Mitsubishi i cells are both blended cathode powder cells. (perhaps Nissan is using a layering trick, to improve short duration power)
Manganese Spinel batteries longevity is very dependant upon electroyte, long life LTO batteries often are Manganese Spinel based, but because they have a different -ve anode, they can use a different electroplyte, and its becasue they use a different electrolyte that they are so robust. When Nissan states they have tweaked electroylte, it means that there could be significant improvement...all else being equal.
The general principle is that by doping -> capacity is traded for robustness
ALL Commercial Manganese Spinel cathodes are doped, the reduction in capacity is about 20% below theoretical non doped manganese spinel. This is primarily achieved by slightly elevating the Li content, it also is achieved by adding small amount of Al, Mg, Ti, Ni etc.
The robustness is improved, which generally means temperature tolerance, cycle life, rate capacity and safety all improve at the same time, BUT energy capacity is reduced and the supply is more niche.
Blending a nickel based cathode (NCA, NMC) into a manganese spinel mix improves both robustness and energy capacity, but then adds further safety issues and higher costs. Nissan LEAF cells and Mitsubishi i cells are both blended cathode powder cells. (perhaps Nissan is using a layering trick, to improve short duration power)
Manganese Spinel batteries longevity is very dependant upon electroyte, long life LTO batteries often are Manganese Spinel based, but because they have a different -ve anode, they can use a different electroplyte, and its becasue they use a different electrolyte that they are so robust. When Nissan states they have tweaked electroylte, it means that there could be significant improvement...all else being equal.