Electric Self Launch System

On Friday, June 8, 2018 at 4:50:33 PM UTC-4, Emir Sherbi wrote:

INR and IMR, depending on the flight mission.


https://breazy.com/products/samsung-...50-25r-2500mah

INR 18650 2500mah Battery (2 Pack) - Samsung

20 amps of continous discharge, the Samsung 25r has been the go to battery for most vapers because of its authenticity and its transparent rating system. In terms of cell degradation the Samsung 25r has been a reliable source of power.

On Friday, June 8, 2018 at 6:30:29 PM UTC-5, son_of_flubber wrote:
On Friday, June 8, 2018 at 4:50:33 PM UTC-4, Emir Sherbi wrote:

INR and IMR, depending on the flight mission.


https://breazy.com/products/samsung-...50-25r-2500mah

INR 18650 2500mah Battery (2 Pack) - Samsung

20 amps of continous discharge, the Samsung 25r has been the go to battery for most vapers because of its authenticity and its transparent rating system. In terms of cell degradation the Samsung 25r has been a reliable source of power.

Flub, are you implying this project is vapor ware?

On Friday, June 8, 2018 at 8:28:04 PM UTC-4, wrote:

Flub, are you implying this project is vapor ware?

Not at all. I think it is brilliant that millions of vapers have volunteered to do rapid discharge testing of INR battery technology. And a mass market battery like this should benefit from manufacturing economies of scale and competition.

Interesting additional battery chemistry info.....

https://batterybro.com/blogs/18650-w...ally-explained

On Friday, June 8, 2018 at 6:30:32 PM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
Interesting additional battery chemistry info.....

https://batterybro.com/blogs/18650-w...ally-explained

And here is a lot more detailed info:

http://batteryuniversity.com/learn/a...of_lithium_ion

While the safety of IMR and INR are good, they are not as good as LFP.

Tom

Yes, they are very reliable and stable. They have very long life cycle. But the energy density is lower. For the same capacity you have to think in more than 60% of weight increase.

On Saturday, June 9, 2018 at 11:54:06 PM UTC-4, Emir Sherbi wrote:
Yes, they are very reliable and stable. They have very long life cycle. But the energy density is lower. For the same capacity you have to think in more than 60% of weight increase.

I'd be very happy to have something soon that could sustain 30 minutes of flight at best glide speed. Maybe I'd upgrade to self-launch later when higher energy density batteries become available, but maybe not.

The 'best' is the enemy of the 'good enough'.

Having learned my lesson with Betamax, I'm looking for the VHS of electric propulsion. My glider is 20 years old. There is a limit to how much I want to sink into it.

"I'm looking for the VHS of electric propulsion."
And we wonder why we're decades behind the Europeans...

Yeh, waiting for an inferior quality system that is more popular is a very US approach.

El domingo, 10 de junio de 2018, 21:30:15 (UTC-3), son_of_flubber escribió:
On Saturday, June 9, 2018 at 11:54:06 PM UTC-4, Emir Sherbi wrote:
Yes, they are very reliable and stable. They have very long life cycle. But the energy density is lower. For the same capacity you have to think in more than 60% of weight increase.

I'd be very happy to have something soon that could sustain 30 minutes of flight at best glide speed. Maybe I'd upgrade to self-launch later when higher energy density batteries become available, but maybe not.

The 'best' is the enemy of the 'good enough'.

Having learned my lesson with Betamax, I'm looking for the VHS of electric propulsion. My glider is 20 years old. There is a limit to how much I want to sink into it.

For our design, having only 30 minutes of sustained flight or selflaunch and having 1 hour of sustained flight is the same technological challenge.
The only thing that changes is the final price.

20 years old is like new, we are about to install it on a 35 years old Pegasus.