One pack, two chemistries
Nio, a Chinese electric vehicle maker, began selling a battery pack that mixed 2 different lithium ion chemistries inside 1 pack, starting September 2021. The 75 kilowatt hour pack combined ternary lithium cells, the industry term for a nickel manganese cobalt chemistry, with lithium iron phosphate cells, called LFP, in the same pack, and Nio sold it in 3 models, the ES8, ES6 and EC6. Nio states the pack reached 142 watt hours of energy for every kilogram it weighs, 14% denser than the single chemistry pack it replaced, and lost 25% less driving range in cold weather than an LFP only pack of the same size. The mixed pack cost buyers no more than the pack it replaced.
What each chemistry trades away
Battery makers mix chemistries because none of the 3 most common lithium ion types wins on every measure. Battery University, an independent testing reference site, gives energy density ranges of 90 to 120 watt hours per kilogram for LFP, 150 to 220 for nickel manganese cobalt, and 200 to 260 for nickel cobalt aluminium, called NCA. LFP also starts breaking down at the highest temperature of the 3, 270 degrees Celsius against 210 and 150, and lasts the most charge and discharge cycles before its capacity falls off, 2,000 or more against 1,000 to 2,000 and 500. LFP is the safest and the longest lasting of the 3 chemistries and also the least energy dense, which is why Nio paired it with a denser chemistry instead of using it alone.
None of these 3 rows is a dual chemistry pack on its own. This chart shows the density gap between chemistries, the reason automakers have tried combining them. Nio own pack does not fall inside the LFP row alone, because it also carried ternary cells.
Show the numbers
| Lithium iron phosphate | 90 to 120 watt hours per kilogram |
| Nickel manganese cobalt | 150 to 220 watt hours per kilogram |
| Nickel cobalt aluminium | 200 to 260 watt hours per kilogram |
Why the mix did not last
By March 2024, Nio replaced the mixed pack with a new 75 kilowatt hour pack built from LFP cells only, a change CnEVPost described as driven by cost. BloombergNEF, a market analyst firm that publishes an annual battery price survey, put average nickel manganese cobalt pack prices at 128 dollars per kilowatt hour against 81 dollars for LFP in 2025, 58% more for the nickel chemistry, a MAOWCE calculation from those 2 figures. Dropping the pricier chemistry only made sense once Nio closed the gap the ternary cells had covered. The all LFP pack charges faster, reaching 170 kilowatts of maximum charging power against 140, and needs 27 minutes to charge from 10% to 80%, down from 30 minutes. It took Nio 2 years of work on charge reading software before the all LFP pack could estimate its remaining charge as accurately as the ternary cells once did.
A second attempt, without a car yet
The idea did not end with Nio. CATL, the company that supplies much of the electric vehicle industry with battery cells, announced its own dual chemistry pack design in April 2025, called Freevoy, placing 2 different battery systems inside 1 pack in 3 named combinations. One pairs a sodium ion cell, which CATL calls Naxtra, with an LFP cell for cold weather range. Another pairs a nickel manganese cobalt cell with an LFP or a second nickel cell, reaching a stated 1,500 kilometres of range and over 180 kilowatt hours of capacity, 3 times the 500 kilometre range CATL states for the Naxtra cell running alone, a MAOWCE calculation from those 2 figures. A third combination pairs 2 versions of LFP cells rather than 2 different chemistry families, reaching a stated 1,000 kilometres of range. CATL has not named an automaker or a car model building any of the 3 combinations.
These are CATL own stated figures for its own product, not independently measured. The middle bar, Freevoy LFP LFP, pairs 2 versions of the same lithium iron phosphate chemistry, not 2 different chemistry families, unlike the third bar. No automaker or car model has been named as building any of the 3 combinations.
Show the numbers
| Naxtra alone | 500 |
| Freevoy LFP LFP | 1,000 |
| Freevoy NCM LFP | 1,500 |