Why not fill up with loose cells? They are small, they roll. Couldn't they roll into a ribbed tray and then a rail on both sides clamps them in place and connects them? Or pulled in on a chain like a machine gun loading mechanism?
This is an original idea that I haven't seen elsewhere.
The big issue is that assembling loose cells into a battery pack is a hard enough operation. It must achieve good mechanical properties (the pack must be rigid enough), good electrical contact with the battery terminals (bad contact would ruin a pack, could start a fire as a bad contact could overheat) and good cooling (battery packs heat, so afaik all designs use liquid cooling, which needs very good thermal contact between the cells and the cooling assembly). Loose cells would essentially mean you're feeding the loose cells inside the pack and the pack has some robotic assembly arms that it uses to put the cells in the right places while it achieves the three objectives.
With some different, taylor made cell design you could make this self-assembly easier, maybe even make it mechanically passive - have the cells orient vertically and slide into their places, and then they're locked. But the current cell design is definitely not chosen for this.
>swappable batteries would require a huge engineering effort.
Worked just fine back in 2013.
The people's habits were the only obstacle: owners wanted to retain their own battery pack, instead of getting pre-owned one left by somebody else, in unknown condition. And/or drive over a weird contraption.
Propane technology has matured and stabilised; a 2019 propane tank is no better than a 2009 propane tank, it'll be the same size, supply the same amount of energy, and have the same connectors. A 2029 propane tank will, in all likelihood, be the same.
The same cannot be said of EV battery technology.
So why the Tesla demo video? According to [1] just doing the demo entitled them to $90 million of Californian "ZEV credits", and they never believed in or planned to roll out the technology.
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The other fix would be swappable batteries. But it would require a huge engineering effort.
Why not fill up with loose cells? They are small, they roll. Couldn't they roll into a ribbed tray and then a rail on both sides clamps them in place and connects them? Or pulled in on a chain like a machine gun loading mechanism?
This is an original idea that I haven't seen elsewhere.
The big issue is that assembling loose cells into a battery pack is a hard enough operation. It must achieve good mechanical properties (the pack must be rigid enough), good electrical contact with the battery terminals (bad contact would ruin a pack, could start a fire as a bad contact could overheat) and good cooling (battery packs heat, so afaik all designs use liquid cooling, which needs very good thermal contact between the cells and the cooling assembly). Loose cells would essentially mean you're feeding the loose cells inside the pack and the pack has some robotic assembly arms that it uses to put the cells in the right places while it achieves the three objectives.
With some different, taylor made cell design you could make this self-assembly easier, maybe even make it mechanically passive - have the cells orient vertically and slide into their places, and then they're locked. But the current cell design is definitely not chosen for this.
tailor-made, unless we're talking golf, ha
>swappable batteries would require a huge engineering effort.
Worked just fine back in 2013.
The people's habits were the only obstacle: owners wanted to retain their own battery pack, instead of getting pre-owned one left by somebody else, in unknown condition. And/or drive over a weird contraption.
[1] (loud music warning) https://www.youtube.com/watch?v=H5V0vL3nnHY
I wonder why it bothers people about battery packs, but not propane tanks. They seem to have equal chances of exploding.
Propane technology has matured and stabilised; a 2019 propane tank is no better than a 2009 propane tank, it'll be the same size, supply the same amount of energy, and have the same connectors. A 2029 propane tank will, in all likelihood, be the same.
The same cannot be said of EV battery technology.
So why the Tesla demo video? According to [1] just doing the demo entitled them to $90 million of Californian "ZEV credits", and they never believed in or planned to roll out the technology.
[1] https://www.quora.com/Whatever-happened-to-Tesla-battery-swa... apologies for the Quora link
What if some jerk replaces half his cells with rocks then swaps the pack and you get it?
You have to trust the charging station that you’re getting an equivalent pack in trade. Are incentives aligned to ensure that?
Gogoro has been quite successful with this model.
The difference, of course, is that a scooter takes batteries small enough to swap by hand.
The Gogoro model is really cool and I would love to see it expand to cars. I’m just providing an example of why people might object to the idea.