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Comment by vonklaus | Hacker News Reader

Putting the physics and this product aside, let's go to another core "law": make something people want. What do people want? Better battery life. What are you doing? Finding a worse way to charge a battery.

Quick recap

Problem: Battery life is much shorter than consumers would like.

>Solution: Make better batteries that last longer, are more durable, and can be recycled into new batteries (to keep costs down in the future)

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People want better battery life just like they wanted faster horses.

What they really want is to never have to charge their devices again or worry about a battery. This company is aiming at the core problem, not just a symptom created by current tech.

Radically improving battery life may prove to be a more difficult physics problem than wireless charging. Lithium-ion batteries were introduced in the early 1990s, and for 20 years nobody's been able to come up with a better technology.

Since the early 90s, CPUs have gotten about 1,000 times better. Batteries have gotten about twice as good.

Yea. Batteries are a tough problem.

A battery with the energy density of TNT would be great. Not sure I'd want it sitting on my lap...

You already do. Lithium-ion batteries have 25-50% the energy density of TNT.

https://en.wikipedia.org/wiki/Energy_density (to fill in the missing volumetric density entry, you need to know that TNT has density 1.7 g/cc)

Think you're referencing Lithium (non-rechargeable) batteries. Lithium Ion is much lower.

Even then, they still occasionally overheat and very occasionally catch on fire.

I think my original point still stands.

At 4.6MJ/kg TNT is fairly low energy density compared to e.g. Jet Fuel at 43MJ/kg.

This still makes me think the future may be in fuel cells more than it is in batteries, but by now we were supposed to have fuel cell powered cellphones and laptops and it didn't came to be.

If you include the weight of the oxidizer, it's a wash. Oxygen, with mass 16, is pretty heavy compared with carbon's 12 and Hydrogen's 1 when you have to combine two oxygens with each carbon and one with each pair of hydrogens.

The big win in "energy density" from normal hydrocarbons is that the oxygen is freely available from the atmosphere.

2W smartphone-sized betavoltaics battery is practical, with a possible lifetime of several decades. The problem is it would be a regulation nightmare.

Alternate solution: broadcast invisible energy through the air that your phone can pick up so that it always maintains its charge.

I understand that according to the posted article it's physically impossible for UBeam to operate in an effective fashion without vaporizing everyone in its vicinity, but let's not throw the baby out with the bathwater. We shouldn't discourage creative solutions.

Building better batteries has proven difficult. It's probably useful to continue to explore solutions from conventional and unconventional angles (at least as long as they are theoretically possible).

Or - make lower power devices?

The economics are interesting, how much would it cost to make a lower power device with the same capabilities? Say a 100% improvement in battery life? Or how much would a better battery cost? Say twice the capacity?

If it cost $200 to do this for an iPhone (I have no idea) then why is it that companies don't spend this; the answer has to be that consumers are just not that willing to pay.

Or - it's impossible or would cost $2,000,000 or something!

But, thinking about it, if it costs $2,000,000 now wouldn't it be smart to invest in a company with a plan to reduce that to $20?

Oh wait! Intel!

I'm a skeptic myself here, but you do point out something interesting. Could such a technology be commercially viable if we make assumptions of where device efficiency is going?

All comments I've seen talk about charging today's iPhone. What about iPhones in 5 years time? Is it reasonable to assume that their power consumption will drop enough to make this make more sense? Anyone with lots of knowledge about power efficiency of mobile devices want to chime in?

http://newsoffice.mit.edu/2014/chip-increases-smartphone-bat...

> how much would it cost to make a lower power device with the same capabilities?

Probably not much as we could do this mostly in software. Just throw away the bloated layers of abstraction we have to deal with and you get improved power efficiency. (Example: When I visit certain websites my device uses far more power than when I'm watching a movie.)

Maybe the key use case initially is to keep charged things like remote controls, sensors, other Internet of Things.

Just make the damn battery twice as thick. It's not rocket science, this thickness madness has to stop.

Who wouldn't 2 or 3 cm of thickness for an twofold increase in battery life?

Me. I rarely run out of battery.

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