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Enlarge / Here's what the lithium deposited at the anode looks like under a scanning electron microscope. Full charge in top row, depleted charge in bottom row. (credit: Louli et al./Nature Energy)

Electric vehicles have come a long way in terms of going a long way on a charge. But everyone is still seeking the next big jump in battery technology—a battery with significantly higher energy density would mean more range or lower costs to hit the current range. There is always some room for incremental progress on current lithium-ion battery technology, but there is a lithium holy grail that has remained out of reach for decades: ditching its graphite anode to shrink the cell.

A lithium metal battery would simply use solid lithium as the anode instead of requiring a graphite framework for lithium atoms to tuck into as the battery charges. The problem is that the lithium doesn't form an order surface during recharging, so the battery capacity drops drastically—declining to 80 percent within 20 charge cycles in some configurations. Rogue lithium also tends to build up dangerous, branching, needle-like structures that can pierce the separator between the anode and cathode and short-circuit the cell.

Last year, a Dalhousie University lab group with ties to Tesla developed a lithium metal battery with somewhat better performance. Lithium atoms electroplate onto a copper electrode as the battery charges and then move back into a conventional lithium-nickel-manganese-cobalt cathode as charge depletes. Through a new electrolyte, they were able to get this battery to last about 90 cycles before hitting 80 percent capacity to control the nasty short-circuit problem.

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Fragments of glassy petrified grass and microscopic traces of plant material, dating to around 200,000 years ago, are all that’s left of a Paleolithic hunter-gatherer’s bed in the back of Border Cave. In the same part of the rock shelter, archaeologists found layers of ash with more recent (as in only around 43,000 years old) and better-preserved leaves of dried grass laid on top, as if people had burned their old, dirty bedding and then laid fresh, clean sheaves of grass over the ashes—the rock shelter version of changing the sheets.

The finds shed light on an aspect of early human life that we rarely get to consider. Most of the artifacts that survive from more than a few thousand years ago are made of stone and bone; even wooden tools are rare. That means we tend to think of the Paleolithic in terms of hard, sharp stone tools and the bones of butchered animals. Through that lens, life looks very harsh—perhaps even harsher than it really was. Most of the human experience is missing from the archaeological record, including creature comforts like soft, clean beds.

Beds were burning

Until now, the oldest bedding archaeologists had ever found came from another South African site called Sibudu, where people 77,000 years ago had piled up layers of grasslike wetland plants called sedge, mixed with assorted medicinal plants, and occasionally burned the old layers. Some modern people in parts of Africa also use plants as bedding in similar ways. The Border Cave find shows that people have been making comfy sleeping pallets out of grass for at least 200,000 years—nearly as long as there have been Homo sapiens in the world.

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Do you have celebration plans for Wookie Life Day? According to Disney, it's the galaxy's "most cheerful and magical holiday," so on November 17, the company will celebrate the event on Disney+ with a Lego Star Wars Holiday Special. Set immediately after Rise of the Skywalker, Rey and BB-8 go on a journey through the nine-film timeline that promises to give screen time to goodies and baddies current and past. Except it's all done in Lego, so painted tongues will be firmly in plastic cheeks.

I've been a huge fan of the more irreverent take that Lego brings to the Star Wars universe since the cut scenes in Lego Star Wars II—whose heart wouldn't melt when Darth Vader whips out a Polaroid to prove to Luke that he's really his dad? And the more recent Lego Star Wars: The Freemaker Adventures stands head and shoulders above Star Wars Resistance, at least to this middle-aged nerd.

All of this gives me faith that this new special won't suck. The original Star Wars Holiday Special is widely reviled by fans as the single worst thing to have come from that far, far away galaxy. It was a TV special aired in 1978, long before George Lucas' swashbuckling in space had become the cultural behemoth we know today. The plot involves Han and Chewie visiting Kashyyyk to celebrate Life Day, where apparently they meet his dad (called Itchy) and his son (called Lumpy). I say "apparently" because it never aired in the UK where I grew up, so I was mercifully spared as a child and I've never quite had a big enough masochistic streak to track down a copy in the decades that have followed.