Tesla Shanghai Model 3 May Go Cobalt-Free Using CATL's LFP Cells — Diving Deeper
With continuing chemistry advances, LFP cells are now starting to reach energy densities (both in weight and volume) that can make good sense for decent-range passenger electric cars, especially those which use energy efficiently, like the Tesla Model 3 SR+, which has a 250 mile EPA range rating.Switching one of Tesla’s highest0volume products (Shanghai Model 3 Standard Range) over to entirely cobalt-free LFP cells — now that LFP chemistry has reached the threshold energy density — will obviously be a win in this respect.CATL’s LFP packs are reportedly already at >20% cost advantage per kWh, compared to their NCM 811 packs, according to Autohome:We know that Tesla has its own approach to battery packaging for its traditional NCA cylindrical cells, so it will be interesting to see how they work with CATL LFP cells.
Tesla is in talks with battery producer CATL* to supply lithium-iron-phosphate (LFP) cells for the Shanghai-made Tesla Model 3, according to a report by Reuters. LFP cells are slightly less energy dense than Tesla’s typical NCA cells, but are cheaper, simpler to package, and require no scarce minerals (cobalt and nickel). They are ideal for further reducing the cost of the Tesla Model 3 Standard Range Plus whilst still providing adequate range.

Lithium-Iron-Phosphate Battery Pros & Cons

All lithium-ion cell chemistries are gaining steady improvements in energy density and benefiting from reductions in cost. Until now, for weight-sensitive EV applications, lithium-ion cells with nickel-cobalt-manganese (NCM) or nickel-cobalt-aluminium (NCA) cathodes have typically been favoured for their higher energy density.

The slightly less energy dense iron-phosphate (LFP) cathodes have been well suited to electric buses and other heavy vehicles (sanitation trucks, etc.), which have modest range requirements but demanding duty cycles and have taken over 90% of this market. LFP typically can be charged and discharged at higher power levels than their NCM and NCA cousins (let’s call these NCx), and they can endure more use cycles before degrading, giving a longer life in high-duty applications such as buses.

With continuing chemistry advances, LFP cells are now starting to reach energy densities (both in weight and volume) that can make good sense for decent-range passenger electric cars, especially those which use energy efficiently, like the Tesla Model 3 SR+, which has a 250 mile EPA range rating.

Although the ~55 kWh pack of the SR+ with LFP cells may weigh perhaps 40–60 kg (around 10-15%) more than the NCA version of the pack, this is only ~3% of the weight of the overall vehicle, and still well under the weight of the Model 3 Long Range variants. The slight added weight is easily compensated by adding another 1 or 2 kWh of energy to keep the overall range the same, and perhaps tweaking the motor peak power to keep peak acceleration the same.

The higher energy density of batteries using NCx chemistries still gives them the edge for EVs needing to offer more energy for range closer to 300 miles (or more). Tesla’s Long Range variants will continue to use these and emerging high-density chemistries for the foreseeable future.

In EVs that don’t need the most extreme energy densities, LFP has advantages of long life, high charging rates, and, perhaps most importantly, cost competitiveness with no risk of any mineral supply constraints, either now or in the future.

No Mineral Constraints

The cobalt supply chain required for NCx batteries is famously complex. Commercially viable cobalt deposits are uncommon globally, and some of the most viable are found in the Democratic Republic of the Congo (DRC), which supplies around two-thirds of the global cobalt market. Although most DRC supply is from modern mining techniques, as of 2016, up to 20% of supply was from “artisanal mining” often involving children and unsafe working conditions. Being associated with this form of mining obviously caries reputational risk for automakers (amongst other industries that use batteries), even the ones (like Tesla) that have committed to not sourcing cobalt from this region or other regions with such problems. Also, since it’s not always possible to have 100% accurate supply-chain tracking, Tesla and other automakers have rightfully been under pressure to reduce cobalt content in cells.