Anyone know what energy the x-ray source is in their system? Seems really well designed, but if it doesn't have energy energy to penetrate the devices we need to scan, none of that will matter.
They don't mention anything on their website, but I guess - from looking at their machine - that they use an x-ray source which goes to the range of 150kV, since they also show larger items with more metal volume being scanned.
What a great concept for explaining the inner workings of everyday things. From a product perspective, what a dream to have that available to take the mystery out of what you do. I'm thinking of other hidden mechanisms that people use every day that it would be socially helpful to understand, and the sponsorship ops must be amazing. I suppose there's just some people you can't convince, so a 5G transmitter might not be a great example, but maybe a speed enforcement gun, the secure element on an iphone, SIM, or chip and pin card, the brake caliper of a car with regenerative braking, a high end espresso machine, a top tier audio amplifier, etc.
> We used the measuring tools in our Voyager analysis software to decode the model number: it seems to mean that the battery is 21mm in diameter and 70mm tall.
I'm pretty sure that sentence was supposed to be a joke. First of all, everybody knows this, secondly you really don't need a CT scanner to measure the diameter of a thing.
You led me down this rabbit hole [1] Curious choice my GM as I thought the LiPo packs were more prone to distortion/swelling which can cause the membranes break and the battery to short.
That's interesting and somewhat surprising. I'm not knowledgeable about battery design by any means, but I would have thought that there would be a better way to make a battery pack for a car than connecting thousands of small batteries together.
if I remember my basic chemistry, batteries don't deliver voltages at the level of 10/20/100v directly often, its more commonly 1/2v or 0.5v class voltages. You have to have a much more 'aggressive' chemical reaction to deliver higher voltages. And, the same with current: a single surface between two reacting things delivers less current. Its a function of surface area. Same with capacitance: you sometimes need 'more' surface to big up the effect.
Therefore all you have is stacking it up. parallel or serial, thats what there is to get higher voltages, more current draw, longer life per-cell.
Inside a lead acid battery its multiple surfaces, sub-cells. It's normal. inside almost any domestic battery I suspect its sub-cells, sub-cells all the way down.
A giant roll of surface, to increase the area in contact might be one way of getting "more" in terms of current draw or lifetime. I bet that its voltage remains close to the constant in this, hence Tesla "stacking" up the rolled cells, to boost voltage.
The Nissan Leaf uses larger cells [1], each roughly the size of a ream of printer paper. So there are real car designers who agree larger batteries are worth considering.
Of course, the Leaf makes a bunch of other decisions that are different to Tesla - lower price point, smaller battery/reduced range, air-cooling batteries instead of water-cooling, a (now abandoned) battery lease scheme, and suchlike.
Using standard form factors and manufacturing techniques made it much easier for Tesla to get batteries off the ground through their partnership with Panasonic. The extra space left by the gaps between cells also has the advantage of being ideal for cooling (battery performance and safety is correlated to temperature).
This strategy is one of the remarked upon things when I first heard of Tesla (something like “this California startup is powering their electric car with laptop batteries”) ironically laptops have almost all transitioned to lithium polymer (pouch cells) instead of the 18650s they used back then. Not all car manufacturers use teslas standardized cell technique, as it does have some downsides. I guess time will tell, but I doubt Tesla will abandon this technique any time soon.
Separating the cells allows makes it easier to cool them. It also provides more inert metal between them in case of fire.
A certain amount of stacking is necessary to get up to a decent voltage, as others have pointed out. But even "100 brick-sized cells" would be a more dangerous prospect than "thousands of 18650 cells".
I have some LiFePO4 batteries powering my laptop, and onboard electronics on my boat. They are very heavy, but have a super long life. Often forgotten, they are used a lot in automotive applications!
From a technical standpoint that makes a lot of sense. I think the main obstacle there is that Tesla doesn't (as far as I know) actually make LFP batteries. The ones they use in their cars come from CATL. Tesla could just buy batteries from CATL and package them in a Powerwall product, but they might not be interested in doing that since there's a big risk that CATL or some other manufacturer could make an identical product without the Tesla brand and sell it at a much lower price.
There's a theory that Powerwall was just a way for Tesla to not waste their excess battery manufacturing capacity when car production wasn't keeping up. I don't know how true that is, but if so there isn't much of a need for them to figure out how to sell CATL's excess battery supply.
Readit News
https://www.youtube.com/watch?v=n564Cw0lHLk
*source: I work with two of the machines here: https://www.bruker.com/en/products-and-solutions/microscopes... (and one more from Bruker which is so old that they don't show it on their website anymore).
Or they could just read https://en.wikipedia.org/wiki/Battery_nomenclature, which describes the relevant IEC standard.
[1] https://cleantechnica.com/2018/07/08/tesla-model-3-chevy-bol...
Therefore all you have is stacking it up. parallel or serial, thats what there is to get higher voltages, more current draw, longer life per-cell.
Inside a lead acid battery its multiple surfaces, sub-cells. It's normal. inside almost any domestic battery I suspect its sub-cells, sub-cells all the way down.
A giant roll of surface, to increase the area in contact might be one way of getting "more" in terms of current draw or lifetime. I bet that its voltage remains close to the constant in this, hence Tesla "stacking" up the rolled cells, to boost voltage.
Of course, the Leaf makes a bunch of other decisions that are different to Tesla - lower price point, smaller battery/reduced range, air-cooling batteries instead of water-cooling, a (now abandoned) battery lease scheme, and suchlike.
[1] https://www.google.com/search?q=nissan+leaf+cell&tbm=isch
A certain amount of stacking is necessary to get up to a decent voltage, as others have pointed out. But even "100 brick-sized cells" would be a more dangerous prospect than "thousands of 18650 cells".
That seems like a missed opportunity for a watercooling pipe, or anything else to use that space effectively.
Performance assessment of a passive core cooling design for cylindrical lithium-ion batterieshttps://doi.org/10.1002/er.4061
You can only have a roll that long before tension from anode expansion will start mechanically damaging it.
Manufacturers intentionally leave some free space to let the roll expand, and shrink
They'd be ideal for home batteries you'd think - I wonder when they'll switch the Powerwall.
There's a theory that Powerwall was just a way for Tesla to not waste their excess battery manufacturing capacity when car production wasn't keeping up. I don't know how true that is, but if so there isn't much of a need for them to figure out how to sell CATL's excess battery supply.