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Chinese cells are like illicit drugs: quality varies widely and it's hard to know what someone is getting. I bought 4 laptop batteries from Amazon and all had overstated capacities of the 18650 chemistries... some had 2000 mAh (10% overstated), others 1800 (22% overstated) , when the 4s3p packs were marked "8800 mAh." I tested the cells individually, and they came out to about 85-99% of spec. The problem is also in the manufacturing because I have zero confidence in these cells not development crystals under anything more than 0.2C dis/charge and lower temperatures.

I think we need an independent UL/CE for evaluating and lifecycle testing and certifying cells are less likely to short out or die prematurely by digging deep into how a battery is made against its specifications, conducting MTTF tests and many other tests and approaches for holistic grading and improvements. Otherwise, fake and shoddy cells will continue to flood the market with phony and dangerous goods. It can't be leveraged as a bureaucratic industry or incumbent protectionism, but to keep standards high as are for all other wall-powered devices. This will knock players whom can't or won't make good products out of the supply-chain, but they deserve it.


There is significant effort (and progress) in standardizing and contrasting test methods [1]. This usually constitues a good first step in a market of lemons. [1] http://energy.gov/sites/prod/files/2014/09/f18/es_cunningham...


Can't wait to buy the plastic battery holder grids for Tesla-sized cells. My first 18650 pack is made from 4 laptop batteries and is capable of about 63 A at 0.2C.


Just out of curiosity… whaaat does this comment mean? Are you building some kind of railgun or something?


Just curious, how much damage could a domestic terrorist do with a railgun made from consumer parts?


Railguns are terrible and conventional firearms are much more widely available. If you want a futuristic terror weapon powered by batteries, build a multiple-watt laser. Take down planes by blinding the pilots! Fire it at a glass sculpture in a shopping mall to give thousands of people life-ruining sight loss!


I thought railguns could shoot projectiles with speeds faster than almost anything. And since they are all about stored electricity inducing magnetism can't a terrorist just charge up a huge capacitor like battery for a year and then release a shit ton of energy in the form of a uranium or heavy lead slug??


Yes, although for terrorism purposes why is this tactially useful given the high cost and complexity? It's not particularly easy to build a 3km/s railgun in your garage, and the power storage ends up being hugely bulky.

Conventional terrorist attacks involving homemade explosives, firearms, mortars, and even rockets have been quite cost-effective enough. I'm more worried about someone combining quadcopters and explosives.


I suppose you're right. Its fun to think about the massive power of railguns and their simplicity though.


Travel patterns mapped before, during and after events helps predict future spread patterns.

Search-engine queries and pharmacy sale histograms by SKUs, especially with geolocation metadata, are vital for pandemic and bioterror surveillance.


I live in a VW somewhere in Silicon Valley.

Ask me anything (respectful, non-troll)

EDIT: I don't usually bite, but when I do, I won't eat much.



Not quite as old and cool as an aircooled 22 window DIY EV like the electric samba, just a digijet Vanagon Westy water-boxer plankton-burner. If/when I had 12 grand, I'm ripping the gas motor out and going EV because there's so many free/cheap charging places available now. Plus, climate change and jihaadis.

PS: CA, NJ and others plz vote today. I did yesterday. If you want change, you gotta be counted.


Where do you crap?


Bathrooms in corporate-owned establishments because there's no sense imposing unnecessary costs on independent shops whom cannot best afford it. Plan your day, schedule your meals and surprises are reduced. And for emergency or actual camping use only, I also have a compact, compostable toilet with the disposable bags (it's just a frame and disposable bags).

On a slightly different subject, I suggest anyone considering living a habitable vehicle not use on-board plumbing or sewage systems because they're messy, time-consuming and expensive to maintain. The vehicle I use only has a water tank but I still use water-store RO water in a washable refrigerator bottle. Using a tank and sink system requires flushing and sterilization periodically, and is often awkward to fill sanitarily.


Do you mean a RV? First serious question: how do you manage your social life?


I don't live in an RV, but ~0% of my social life takes place at home. I just sleep there.


Suppose you want to bring a date home and have sex. What's been the typical reaction to the "van down by the river"?


"sex van" is sort of mid-range sketchy, and a whole lot better than "sex tarp".

https://xkcd.com/1101/


Rent a hotel room?


Thanks bro, I got this. :)

Although I do have an LED spinning light ball, an old tape-player radio and the world's smallest dance floor.


VW doesn't make a big RV. :)

The same as anyone else. It sounds like you're trying to imply something like stereotypes or biogtry. What are you really asking?


Where do you park?


what rental price would get you out of the VW?


Airbnb, uber or is that an offer to cofound an app to pay to live with startup people?

Personally, I'd never let someone rent it without a massive security deposit and a very profitable rate because parts are rare, fragile and expensive.


I think he was asking what rental price would have you choose to live in a rental house/apartment instead of the VW. Eg, to what extent is your choice out of economic necessity, and what are you willing/able to spend to live in a more conventional residence?

Obviously, location matters.


Why on earth does the military-industrial complex need to spend money on a duplicate, irrelevant technology? I worked at Trimble Nav in the radio group, and the POTUS has the ability to increase selective available (SA) to an enormous number (which can be defeated by differential/kinematic corrections, but was set to 0 by executive order under Clinton) or disable the unencrypted channel entirely for a particular region or the entire planet (which includes space). WTF!


Satellites designed after May 2000 no longer have SA capability.


because it's pointless and since areas can be and have been turned off for non-military receivers.


No, it has never been turned off since it first went to full availability [1].

[1] http://www.gps.gov/support/faq/#off


> Why on earth does the military-industrial complex need to spend money on a duplicate, irrelevant technology?

Why on earth do data centres need to spend money on duplicative, irrelevant RAID-1 disks?


Presumably whatever they are testing will work on other, similar systems over which the US military does not have control.


Sam will give us the straight dope on all of InfoWars (lol) favorite conspiracy theories. ;)


DRM, bleh.

It's sad that open source browsers and open web standards folks are doing the bidding of corporate interests. At this rate, we won't be able to own a permanent, portable "license" to a work, only rent a license locked to a particular device on a certain platform.


You might. There is a blockchain-based technology called "colored coins", and a few startups working to use it for DRM/digital ownership. It will be platform-independent.


Actually, there already is, it's called OpenADR.

http://products.openadr.org/?posts_per_page=-1

See also Ecobee vs. Nest: http://controltrends.org/controltrends-news/news-and-informa...


"Have you seen the swimming pool on the roof?"

;)


Yup. Having many distributed li-ion battery walls charging at night for peak assist during the day is one way to level out demand and make the energy infrastructure more resilient in a Google-servers-like way.


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