Technical brief · Li-ion cells

Cobalt battery vs ternary battery : what really separates a premium cell from a standard one

Q: Is cobalt present in both chemistries?

Yes, but in different proportions. LCO is entirely cobalt-based; NMC only contains a fraction of it, the rest being nickel and manganese. This is what makes NMC cheaper to produce.

Q: How do I know which one to choose?

For behaviour closest to the original and the best perceived battery life: Cobalt. For a reliable replacement at the best price: ternary. If unsure for your model, contact Place du Mac.

Q: Does safety depend on the chemistry?

Partly: LCO has slightly lower thermal stability, NMC is stabilised by manganese. But real safety comes mainly from the BMS (built-in protections) and compliance with UN 38.3 transport standards, required for every battery.

« Cobalt », « ternary », « lithium-ion »… behind these words hide different cathode chemistries, which do not behave the same way inside a Mac. We open up the cell and explain, material by material, why Place du Mac distinguishes a Cobalt (premium) range from a ternary (standard) range.

Place du Mac— Technical brief— 12 July 2026— 8 min read

The essentials

A « Cobalt » battery uses a cathode made of lithium cobalt oxide (LCO), the classic chemistry of portable electronics : stable voltage, excellent volumetric energy density, faithful to the Apple original. A « ternary » (NMC) battery blends nickel, manganese and cobalt : an excellent chemistry, more economical, but one notch below when it comes to reproducing factory behaviour in the slim format of a Mac. Hence our premium Cobalt range and our standard ternary range.

The starting point

In a Li-ion battery, everything comes down to the cathode

Whatever the brand, a lithium-ion cell always relies on the same principle : two electrodes separated by an electrolyte, and lithium ions that shuttle back and forth from one to the other.

Anode (− pole) : almost always graphite. It is the part that changes the least from one cell to another.
Electrolyte : a lithium salt (typically LiPF₆) dissolved in carbonate solvents. It acts as the highway for the ions.
Cathode (+ pole) : this is where the difference between « Cobalt » and « ternary » plays out. The cathode material determines voltage, energy density, lifespan and safety.

In plain terms : when a reseller talks about a « Cobalt » or « ternary » battery, they are not talking about the casing, the connector or the flex cable — they are talking about the chemical composition of the cathode. And it is the most decisive variable for the quality you perceive day to day. Counter-intuitive but essential : lithium travels from one electrode to the other, but what « stores » the energy on the positive side is the metal oxide. Hence the importance of the metal used.

The two chemistries

Cobalt (LCO) and ternary (NMC), under the microscope

Same family of « layered » materials (sheets between which lithium inserts itself), but a radically different cathode composition.

Chemistry1

The Cobalt battery — lithium cobalt oxide (LCO)

A cathode of LiCoO₂, abbreviated LCO : the chemistry that powered the first smartphones, iPods, and the original batteries of many laptops. A very regular layered structure : lithium intercalates cleanly between the cobalt oxide layers, which gives perfectly regular insertion/extraction. The result : a high and stable nominal voltage (~3.7–3.9 V) with a very flat discharge plateau — the voltage stays high almost until the end, so the device « feels » a full battery for longer — and an excellent volumetric energy density (best in class per litre), ideal in the slim chassis of a Mac.

Trade-off : high cost (cobalt is expensive) and lower thermal stability — hence the need for a serious BMS.

Chemistry2

The ternary battery — nickel-manganese-cobalt (NMC)

« Ternary » (in Chinese 三元, « three elements ») refers to a cathode that combines three metals : nickel, manganese and cobalt (LiNiₓMnₖCoₔO₂, common ratios NMC 532, 622, 811). Nickel boosts capacity, manganese stabilises the structure and improves safety. The nominal voltage is slightly lower (~3.6–3.7 V) and the discharge curve a little more « sloped ». Its energy density by weight is excellent (nickel-rich NMC climbs very high), but by volume, in an ultra-slim format, it generally still trails a good LCO.

Its strengths : controlled cost (less cobalt), good thermal stability, solid cycle life.

Head to head

Cobalt vs ternary, criterion by criterion

There is no « bad » chemistry in absolute terms — NMC powers millions of electric vehicles. The real question : which one best restores the original experience in the specific format of a Mac ?

Criterion	Cobalt — LCOPremium	Ternary — NMCStandard
Cathode metals	Cobalt only	Nickel + Manganese + Cobalt
Nominal voltage	~3.7–3.9 V	~3.6–3.7 V
Discharge curve	Very flat plateau, stable voltage	More gradual decline
Volumetric density (Wh/L)	Excellent — ideal for slim chassis	Good
Gravimetric density (Wh/kg)	High	High to very high (high-Ni)
Thermal stability	Adequate (quality BMS required)	Good (stabilising manganese)
Fidelity to the Apple original	High	Average
Material cost	High (cobalt)	Controlled
Typical positioning	Premium portable electronics	Mid-range, high volume

Day to day

Why it makes a difference on your Mac

Beyond the formulas, here is what the cathode chemistry concretely changes in everyday use.

4 concrete effects

From chemistry to experience

Two batteries advertised at the same capacity do not necessarily behave the same way : the chemistry and the build quality make the difference.

Real battery life

At equal advertised capacity, the volumetric density of LCO better respects the original capacity within the available space.

Reliable gauge

The flat plateau of LCO makes a faithful percentage easier. A gauge that jumps from 40 % to 15 % often betrays a poorly matched cell.

Endurance over time

Capacity retention depends as much on material purity and cell matching as on the chemistry itself.

Safety

Whatever the chemistry, a BMS (overcharge, deep-discharge, short-circuit and overheating protections) and the UN 38.3 standard are non-negotiable.

The myth to bust What many people think — and it is wrong

« Ternary means a poor-quality battery. »

False. NMC is a cutting-edge chemistry — it powers most electric vehicles and professional power tools. On a Mac, it is simply less optimal than LCO at reproducing the slim format and the original voltage curve. So it is not « good versus bad », but « closest to the original » versus « excellent value for money ». That is exactly why we classify it as a standard range, and not as a premium range.

The Place du Mac choice

Two clearly identified ranges

So that you can choose with full knowledge, we distinguish two ranges — both tested, matched to the model’s electronics and shipped with a certified BMS.

Our recommendation

Cobalt range — Premium

LiCoO₂ cathode (LCO)

As close as possible to the original Apple chemistry. Optimal volumetric density for the Mac format, faithful voltage curve, consistent gauge.

Battery life as close to factory as possible
% gauge stable and credible
Original behaviour restored

The best value for money

Ternary range — Standard

NMC cathode (Ni-Mn-Co)

A robust, proven chemistry for a functional and economical replacement, when budget takes priority over « original » restitution.

Price more accessible
Reliability proven
Same standard of testing and BMS

If you remember only one thing

The difference is not marketing : it is chemistry.

Cobalt (LCO) and ternary (NMC) are two genuinely different cathodes, with measurable behaviours. LCO keeps the edge for recovering the battery life and the feel of a factory battery in the slim format of a Mac ; NMC offers a reliable replacement at the best price. Unsure about your model ? Contact us, we’ll point you in the right direction.

Frequently asked questions

Cobalt vs ternary battery : your questions

Does « ternary » mean lower quality ?

No. NMC is a cutting-edge chemistry that powers most electric vehicles. On a Mac, it is simply less optimal than LCO at reproducing the slim format and the original voltage curve. Hence its classification as a standard range with us.

Is cobalt present in both chemistries ?

Yes, but in different proportions. LCO is entirely cobalt-based ; NMC only contains a fraction of it, the rest being nickel and manganese. This is precisely what makes NMC cheaper to produce.

Does a battery have more « volts » depending on the chemistry ?

The nominal voltage differs slightly (LCO ~3.7–3.9 V, NMC ~3.6–3.7 V), but the final battery is calibrated to deliver the voltage your Mac expects. What mainly changes is the shape of the discharge curve, not compatibility.

How do I know which one to choose ?

You want behaviour closest to the original and the best perceived battery life : Cobalt. You are looking for a reliable replacement at the best price : ternary. Unsure for your model ? Contact us.

Does safety depend on the chemistry ?

Partly : LCO has slightly lower thermal stability, NMC is stabilised by manganese. But in both cases, real safety comes mainly from the BMS (built-in protections) and compliance with transport standards (UN 38.3), which we require for every battery.

Take action

Need a battery for your Mac?

Tested, matched to your model and guaranteed — pick your range.

Premium batteries →Standard batteries →

Place du Mac technical brief — a plain-language look at lithium-ion cathode chemistries (LCO / NMC). The voltage and energy-density figures are typical orders of magnitude ; actual performance depends on the cell, the BMS and the build quality. « Cobalt » and « ternary » refer to the cathode composition, not the casing or the electronics. Apple, Mac and MacBook are trademarks of Apple Inc. ; Place du Mac is an independent repairer, not affiliated with Apple Inc.