Is battery life only an issue due to charging times?

[James]

So I got re-interested in super capacitors the other day. After the Tesla fiasco with Elon Musk and the NYT playing he-said she-said, it made me think about why there is such range anxiety in electric vehicles.

In my opinion it is because unlike normal gasoline powered vehicles, you cannot quickly recover from running out of fuel. You must be tethered, even with a "supercharger" to a charging station for at least an hour if not several hours. It is the same way with most mobile devices. Un-tethered time is nice, but it would seem that what makes us focus on battery life isn't that we absolutely must stay away from a wall charger, but that we don't want to be tied to it for significant periods of time.

With super capacitors replacing batteries, we could quite literally charge devices in seconds instead of hours. Would this change the way you feel about battery life? I know it would for me. If killing the battery in my phone meant a quick 30 seconds-1 minute charge time to completely refill the energy reserves, I wouldn't care about running out mid-day.

How about you? Where do you fall on the charging time is what causes batter-life-anxiety issue?

[proxops-pete]

I have no issue charging it overnight... it just doesn't last throughout the day, and that's where my problem lies...

[ImaNihilist]

My understanding of super capacitors is that they charge quickly, but only store a fraction of energy. So you are just trading an 8 hour battery with a 2 hour charge time for a 2 hour batter with a 5 minute charge time, or something to that effect. Those ratios are all messed up, but that was my understanding.

[James]

My understanding of super capacitors is that they charge quickly, but only store a fraction of energy. So you are just trading an 8 hour battery with a 2 hour charge time for a 2 hour batter with a 5 minute charge time, or something to that effect. Those ratios are all messed up, but that was my understanding.

Current technology apparently puts them basically on par with traditional battery technology (lithium Ion/polymer). I'll dig up what I found the other day, but energy densities have more or less reached parity.

[ImaNihilist]

Current technology apparently puts them basically on par with traditional battery technology (lithium Ion/polymer). I'll dig up what I found the other day, but energy densities have more or less reached parity.

Really? I thought it was like 10-25% of a standard battery. I also know that those little graphene strips have a crazy high discharge rate. So the battery basically discharges whether you use it or not.

I always thought of them as two very different kind of technologies, not that one would be able to replace the other.

[James]

http://io9.com/5987086/meet-the-scie...ange-the-world

That's the latest thing right now, at "200 W per cm-3". From a quick search, Li-Ion is 300mW/h - cm3. So I'm not sure if that's a typo, or a different form of measurement, etc.

Assuming it's just a typo, that's 66% of Lithium-Ion. I could have sworn I found something that matched them within say 10%, but I'll fall back to what I just found on the Internet.

*Edit: And just for fun: http://www.maxwell.com/ultracapacitors/

[kpxgq]

from my understanding of current li-ion tech, faster charging (ie higher amps at the same voltage) will also kill the battery faster.. ideally you would do a slow charge to keep the battery healthy

i have 2 USB chargers by my nightstand for this very reason... a regular 1amp charger for overnight charging and a 2amp charger if i need a quick charge on my devices

[kujoe2002]

For me, having shorter battery life (even with fast recharging) would mean that I would need to carry a charger of some sort with me at all times. I hate carrying more stuff than I must so having a long battery life is essential. It's become one of the key factors when I purchase electronics now. I'd rather carry an extra fully charged battery than need to charge because if you have just the USB cable, you'd need to have access to a live USB port. The AC charger is much bulkier to schlepp around than a second battery.

[James]

I've been going back and forth on this some more, and I still come back to the fact that if I could recharge in seconds instead of hours, I wouldn't care about having to find an outlet every now and then. Because I'm not stuck at an outlet, I just walk up to it, plug in, wait a few seconds, unplug and I'm good for a few more hours of usage. That still appeals to me.

[kpxgq]

For me, having shorter battery life (even with fast recharging) would mean that I would need to carry a charger of some sort with me at all times. I hate carrying more stuff than I must so having a long battery life is essential. It's become one of the key factors when I purchase electronics now. I'd rather carry an extra fully charged battery than need to charge because if you have just the USB cable, you'd need to have access to a live USB port. The AC charger is much bulkier to schlepp around than a second battery.

i used to think this way but im the kind of person who upgrades his gadgets every year or so.. i would end up with a bunch of obsolete batteries every time i upgraded.. now i just carry a a large 10,000mah battery pack when i travel and i have another smaller 3,000mah pack for one day use... its not much larger than a spare battery and i can use it for any USB device not just my one phone

http://www.amazon.com/10000mAh-Light.../dp/B009USAJCC

http://www.amazon.com/Anker%C2%AE-As...dp/B005X1Y7I2/

I've been going back and forth on this some more, and I still come back to the fact that if I could recharge in seconds instead of hours, I wouldn't care about having to find an outlet every now and then. Because I'm not stuck at an outlet, I just walk up to it, plug in, wait a few seconds, unplug and I'm good for a few more hours of usage. That still appeals to me.

some of the better battery packs out there like the 10k anker that i use have a high speed 2/3amp USB port which gets my phone from dead to 50% in a couple of minutes

[kujoe2002]

i used to think this way but im the kind of person who upgrades his gadgets every year or so..

That would gather too much clutter for me. Hell I've been using a Droid 2 phone for the last 3 years and it does everything I want. Too much hassle. I like the theory "if it ain't broke, don't fix it."

[kpxgq]

i just toss my old device on ebay and get about 70% of the value back for my upgrade every year

[PCVSNotebook]

My understanding was that super capacitors are military grade and not allowed to the normal consumer. It is too dangerous to make them available for everyone.

[James]

My understanding was that super capacitors are military grade and not allowed to the normal consumer. It is too dangerous to make them available for everyone.

Uhm.... no.

[PCVSNotebook]

Uhm.... no.

Maybe another type of capacitors then . I am sure I read about them few years ago.