Prior to the launch of the Proton e.MAS 7, we got to learn about the tech that goes into the car.
One of the interesting aspects about electric vehicles is the battery. No other single component has ever come to define the overall cost of building a vehicle quite like the battery of an EV. We spoke to engineers at Geely and Proton who confirmed to us that the battery pack still makes up some 40% of the bill of materials, even after countless advancements over the last decade. It’s also interesting to understand the chemistry and suppliers behind a particular EV’s battery pack as there are only a handful of players in the market.
For the Proton e.MAS 7, the supplier is none other than Geely themselves. They created an alternative to BYD’s Blade Battery which they’re refer to as “Aegis Short Blade” battery in more recent marketing materials. Initial press releases simply refer to the new battery as Geely Auto’s New Short Blade EV Battery Technology.
Longevity Improvement
Besides the supplier, the chemistry is noteworthy too. It uses Lithium Iron Phosphate (LFP) chemistry instead of the more energy dense Nickle Cobalt Manganese Oxide (NCM) chemistry found in most Western and Korean EVs. However the trade off is worth it to some. LFP batteries can be repeatedly charged to 100% without significant battery health degradation. Geely’s internal testing shows that after 921 cycles (400,000km of range), the battery still held on to 90.5% of its battery health.
Safety Improvement
Besides that, LFP batteries like the Aegis Short Blade Battery tend to be safer in a crash. Puncture tests show no fire, smoke or explosion after the pack is pierced with multiple nails. Temperature also stays within relatively safe bounds. In Geely’s design, ‘self-fusing’ tech on the electrode surfaces block short circuits in the event of an accident. An aluminium foil layer fuses to the battery diaphragm to create an insulating layer that prevents dangerous thermal runaway events that lead to battery fires.
To prove their point, Geely shot the battery with a 5.8×42mm infantry rifle bullet and it didn’t explode. It was also punctured by eight steel needles in unison, each with a diameter of 5mm and left to stand for 1 hour. No explosions or fires.
Packaging Improvement
Geely/Proton was keen to point out that their design featured shorter individual blade cells that were more energy dense individually. This allows the cells to be packaged better when the shape and volume of the battery pack is constrained, plus it gives you more energy per kg of battery.
Durability Improvement
Besides the safety tests, Geely also put the Aegis battery pack through extreme durability tests that include:
- seawater corrosion immersion
- extreme cold environment
- high-frequency pack bottom scraping
- 26-ton overweight rolling
- single-pack side collision
- fire roasting
Thanks to the cell-to-body integration and 3-layer sandwich bottom guard plate and other built in safety features, the battery survived. Additionally, the strong discharge capacity of the battery allows it to be used more effectively in extreme cold conditions. BYD’s long blade battery drops in capacity retention at -30 degrees celcius to 78.96% while Geely’s short blade battery retains 90.54% of its capacity at that temperature according to Geely’s report.
Endurance Improvement
Another challenge was to get the life cycle of the battery up. Geely’s internal testing shows that it can reach over a 1 million kms of driving range in terms of life cycles. Based on an average of 20,000km of use, this translates to 50 years of driving, a feat increasingly few ICE vehicles can pull off.
Charge Speed Improvement
LFP batteries, for whatever reason, seem to have slower charging rates than their NCM counterparts. To counter this, Geely designed their new battery pack with thin carbon nanotubes. Compared to their LFP rivals, the Geely design goes from 10-80% state of charge in 17 minutes and 4 seconds while their rival tech of similar capacity need 26 minutes to do the same.
Relationship Improvement
Geely also highlighted that this was an entirely in-house design that used different coatings and separators than BYD’s Blade battery design, which ultimately improves its performance. This tech is also BRAND NEW, being revealed to the public only at the end of June 2024, so Proton getting it this early is actually a significant change for the relationship, where in the past Geely’s ‘hand-me-downs’ became Proton rebadged vehicles only after years.
Geely Galaxy E5 (2024) -> Proton e.MAS 7 (2024): 0 year gap
Geely Haoyue (2020) -> Proton X90 (2023): 3 year gap
Geely Emgrand (2021) – > Proton S70 (2023): 2 year gap
Geely Binyue (2018) -> Proton X70 (2020): 2 year gap
Geely Boyue (2016) -> Proton X70 (2018): 2 year gap
