Electric Self Launch System

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.

On Sunday, June 10, 2018 at 10:49:51 PM UTC-4, Emir Sherbi wrote:

For the same capacity you have to think in more than 60% of weight increase.

A lower capacity battery pack will be lighter and cheaper. Maybe that would make INR batteries feasible.

On 06/11/2018 06:37 AM, son_of_flubber wrote:
On Sunday, June 10, 2018 at 10:49:51 PM UTC-4, Emir Sherbi wrote:

For the same capacity you have to think in more than 60% of weight increase.

A lower capacity battery pack will be lighter and cheaper. Maybe that would make INR batteries feasible.


I think he was talking about LFP batteries not being feasible, due to
low energy density.

El lunes, 11 de junio de 2018, 9:37:44 (UTC-3), son_of_flubber escribió:
On Sunday, June 10, 2018 at 10:49:51 PM UTC-4, Emir Sherbi wrote:

For the same capacity you have to think in more than 60% of weight increase.

A lower capacity battery pack will be lighter and cheaper. Maybe that would make INR batteries feasible.


In your case if you want that capabilities it can be arranged.
We are trying to standardize some components but the battery size and shape can be changed without much issues.