👋 Good morning! The craziest ending to a Formula One world championship in memory, in the craziest season. And I said the exact same thing last week. I’m not going to weigh in on the wild rules, appeals, and confusion, but it was pure motor racing entertainment.

Xiaomi talked about this on Friday, but over the weekend I haven’t stopped thinking about how battery tech is taking a small but significant step.

In short:

• Battery technology is more crucial than ever for us, our smartphones, and at a much bigger scale, for electric vehicles.
• The focus is usually on the anode material: while cathode materials have been perfected, increasing the energy density of the formerly graphite anode is the name of the game, without adding considerable expense for rare materials, or safety problems.

But also:

• Xiaomi has announced that its new technology is “High-Silicon Lithium battery technology,” which offers more capacity at the same volume, increasing its battery capacity in phones by up to 10%, starting from mid-2022.
• (It’s on the right, in the image above) 
• How? The high-silicon aspect, Xiaomi says, means “a claimed three-fold increase in the battery’s silicon content.” 
• There’s also mention of a very abstract “fuel-gauge chip” that “helps battery longevity and safety,” somehow. (If there’s a chip that helps battery longevity and safety, why wouldn’t that be in a battery made right now?)

What is high-silicon exactly?

• So, why has no one else offered high-silicon batteries? Why doesn’t Xiaomi have 5x or 10x the amount of silicon?
• I’m not sure exactly, and I welcome readers to write in on this. A look at papers about battery technology suggests that silicon is a “promising anode material for lithium-ion and post-lithium-ion batteries,” but suffers from “a large volume change upon lithiation and delithiation,” or to say it in plain English: it suffers a “huge volume change during the electrochemical process.”
• Therefore, adding too much silicon would require a bundle of tricks to increase volume without safety risks from battery expansion. 
• Other papers suggest adding composites and alloys to match benefits without volume problems.
• So, I don’t know, Xiaomi’s detail here is light and fluffy, but there’s a chance we’ll find out more in time.

👉 The OnePlus Nord 2 CE specs may have just leaked: MediaTek Dimensity 900 chipset and faster wired charging (Android Authority).

🔨 Android phones should have a private “repair mode”: send your phone, not your data (Android Authority).

📁 ICYMI: Foldable Oppo Find N leaks in full, looks like a smol boi (Android Authority).

🍃 “Dyson’s new air purifier convinced me that sometimes it’s worth paying a premium” (Android Authority).

📱 Samsung has named its new phone and appliance business its DX Division: “Device eXperience” (Bloomberg).

🐚 The Log4Shell zeroday, four days on. What is it and how bad is it really? (Ars Technica).

📦 Amazon has explained the outage that took out a large chunk of the internet (Engadget).

🔢 Ok, we missed the live event but wow, the Financial Modeling World Cup or the player-vs-player Excel battle is amazing to watch, although it’s hard to know what’s going on at some points unless you live in Excel (The Verge).

🔥 “We live in hell and this Ubisoft NFT that requires you to play 600+ hours of Ghost Recon is proof” (Kotaku).

🥽 I’m not sure if this is good or not but: MGM Resorts is letting job seekers try out roles using VR as it looks to reduce employee churn (Insider).

📚 Holiday reading: 19 book recommendations from the Ars staff. Huh, I’ve only read two of these, including The Spy Who Came in from the Cold by John Le Carré (Ars Technica).

🔋 “I drove the 800-Volt Hyundai Ioniq 5, the first car on the ‘revolutionary’ E-GMP platform” (Jalopnik).

🌌 Gravitational waves should permanently distort spacetime (Wired).

👨‍🚀 NASA’s new sleeping bags could prevent eyeball ‘squashing’ on the ISS: It sucks fluid out of astronauts’ heads and toward their feet (Engadget).

🎁 “What do you want for Christmas?” (r/askreddit).

Please enjoy this Christmas miracle:

Tristan Rayner, Senior Editor