Ni-Cd Batteries on Satellites
LO-19 (aka LUSAT) after 30 years in space is emitting day and night a strong carrier.
What is amazing that after over 2 millions charge/discharge cycles its vintage NI-CD batteries are still able to receive and hold charge.
It is known that Lithium based batteries usually halve charge capacity after +/- 400 cycles, probably you noticed that on your portable device. https://batteryuniversity.com/_img/content/lithium2.jpg
This is just a comment for future satellite plans if long duration is part of the objective.
73, lu7abf, Pedro
On Fri, Mar 13, 2020 at 06:56:55PM -0300, Pedro Converso via AMSAT-BB wrote:
LO-19 (aka LUSAT) after 30 years in space is emitting day and night a strong carrier.
What is amazing that after over 2 millions charge/discharge cycles its vintage NI-CD batteries are still able to receive and hold charge.
It is known that Lithium based batteries usually halve charge capacity after +/- 400 cycles, probably you noticed that on your portable device. https://batteryuniversity.com/_img/content/lithium2.jpg
This is just a comment for future satellite plans if long duration is part of the objective.
Super capacitors are very quickly maturing and are a possiblity in future missions.
https://batteryuniversity.com/learn/article/whats_the_role_of_the_supercapac...
Also from 2018 https://www.electronicsweekly.com/news/design/will-supercapacitors-supersede...
If a satellite was limited to use only in Sunlight with a small supercap for periods in eclipse to hold config etc. this might be a practical solution now. It's a rapidly changing field.
73, lu7abf, Pedro
73, VA3DB, Diane
We have used NiCds on all of my 4 satellites with no battery problems.
They are robust, and survive all student mistakes and require no Battery management system when paired with a matching solar panel design. IE, as th batteries approach full charge is the same point where the solar panel voltage maxes. Also NiCd's can be safely overcharged at 10% indefinitely with no concern. (you only get an hour in the sun and then 35 minutes eclipse)...
Yes, they are twice as heavy as Lithium, but the advantages FAR outweigh the criticality of Lithium concerns and complexity of the BMS and total failure on overcharge or undercharge.
And MASS is an advantage! PSAT and BRICSAT-1 are identical 1.5U cubesats launched at the same time in May 2015. But PSAT with big C cell NiCd's was made heavier with lead ballast to 2.3kg. BRICSAT (1.7 kg) with lightweight Lithiums has already decayed in November. PSAT is predicted to last 2 more years! Same thing for identical RAFT and MARSCOM cubesats back in 2006. RAFT was ballasted up and lasted TWICE as long as MARSCOM.
For comm satellites, there is no reason to come in under mass. Always ballast up to the maximum the launcher will allow!
Bob, WB4APR
On Fri, Mar 13, 2020 at 5:58 PM Pedro Converso via AMSAT-BB < [email protected]> wrote:
LO-19 (aka LUSAT) after 30 years in space is emitting day and night a strong carrier.
What is amazing that after over 2 millions charge/discharge cycles its vintage NI-CD batteries are still able to receive and hold charge.
It is known that Lithium based batteries usually halve charge capacity after +/- 400 cycles, probably you noticed that on your portable device. https://batteryuniversity.com/_img/content/lithium2.jpg
This is just a comment for future satellite plans if long duration is part of the objective.
73, lu7abf, Pedro _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Another data point.
Falconsat 3 has F size Sanyo NiCads that have survived several instances of being pulled down to less than 1V causing a CPU reset during more than 12 years on orbit. Last time I looked at the telemetry the peak charged voltage was less than .1V / cell below the original voltage. They just keep taking abuse and going, going.
Jim
On 3/14/2020 10:53 AM, Robert Bruninga via AMSAT-BB wrote:
We have used NiCds on all of my 4 satellites with no battery problems.
They are robust, and survive all student mistakes and require no Battery management system when paired with a matching solar panel design. IE, as th batteries approach full charge is the same point where the solar panel voltage maxes. Also NiCd's can be safely overcharged at 10% indefinitely with no concern. (you only get an hour in the sun and then 35 minutes eclipse)...
Yes, they are twice as heavy as Lithium, but the advantages FAR outweigh the criticality of Lithium concerns and complexity of the BMS and total failure on overcharge or undercharge.
And MASS is an advantage! PSAT and BRICSAT-1 are identical 1.5U cubesats launched at the same time in May 2015. But PSAT with big C cell NiCd's was made heavier with lead ballast to 2.3kg. BRICSAT (1.7 kg) with lightweight Lithiums has already decayed in November. PSAT is predicted to last 2 more years! Same thing for identical RAFT and MARSCOM cubesats back in 2006. RAFT was ballasted up and lasted TWICE as long as MARSCOM.
For comm satellites, there is no reason to come in under mass. Always ballast up to the maximum the launcher will allow!
Bob, WB4APR
On Fri, Mar 13, 2020 at 5:58 PM Pedro Converso via AMSAT-BB < [email protected]> wrote:
LO-19 (aka LUSAT) after 30 years in space is emitting day and night a strong carrier.
What is amazing that after over 2 millions charge/discharge cycles its vintage NI-CD batteries are still able to receive and hold charge.
It is known that Lithium based batteries usually halve charge capacity after +/- 400 cycles, probably you noticed that on your portable device. https://batteryuniversity.com/_img/content/lithium2.jpg
This is just a comment for future satellite plans if long duration is part of the objective.
73, lu7abf, Pedro _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Amen.
Jerry Buxton, NØJY
On 3/14/2020 11:53, Robert Bruninga via AMSAT-BB wrote:
We have used NiCds on all of my 4 satellites with no battery problems.
They are robust, and survive all student mistakes and require no Battery management system when paired with a matching solar panel design. IE, as th batteries approach full charge is the same point where the solar panel voltage maxes. Also NiCd's can be safely overcharged at 10% indefinitely with no concern. (you only get an hour in the sun and then 35 minutes eclipse)...
Yes, they are twice as heavy as Lithium, but the advantages FAR outweigh the criticality of Lithium concerns and complexity of the BMS and total failure on overcharge or undercharge.
And MASS is an advantage! PSAT and BRICSAT-1 are identical 1.5U cubesats launched at the same time in May 2015. But PSAT with big C cell NiCd's was made heavier with lead ballast to 2.3kg. BRICSAT (1.7 kg) with lightweight Lithiums has already decayed in November. PSAT is predicted to last 2 more years! Same thing for identical RAFT and MARSCOM cubesats back in 2006. RAFT was ballasted up and lasted TWICE as long as MARSCOM.
For comm satellites, there is no reason to come in under mass. Always ballast up to the maximum the launcher will allow!
Bob, WB4APR
Stumbled on this paper by accident:
http://adsabs.harvard.edu/full/1998ESASP.416..715C
-Mike
On Sat, Mar 14, 2020, 10:02 PM Jerry Buxton via AMSAT-BB [email protected] wrote:
Amen.
Jerry Buxton, NØJY
On 3/14/2020 11:53, Robert Bruninga via AMSAT-BB wrote:
We have used NiCds on all of my 4 satellites with no battery problems.
They are robust, and survive all student mistakes and require no Battery management system when paired with a matching solar panel design. IE, as th batteries approach full charge is the same point where the solar panel voltage maxes. Also NiCd's can be safely overcharged at 10% indefinitely with no concern. (you only get an hour in the sun and then 35 minutes eclipse)...
Yes, they are twice as heavy as Lithium, but the advantages FAR outweigh the criticality of Lithium concerns and complexity of the BMS and total failure on overcharge or undercharge.
And MASS is an advantage! PSAT and BRICSAT-1 are identical 1.5U
cubesats
launched at the same time in May 2015. But PSAT with big C cell NiCd's
was
made heavier with lead ballast to 2.3kg. BRICSAT (1.7 kg) with
lightweight
Lithiums has already decayed in November. PSAT is predicted to last 2
more
years! Same thing for identical RAFT and MARSCOM cubesats back in 2006. RAFT was ballasted up and lasted TWICE as long as MARSCOM.
For comm satellites, there is no reason to come in under mass. Always ballast up to the maximum the launcher will allow!
Bob, WB4APR
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
This is a good catch Mike. I'm saving it to provide to the uni's I work with.
Jim
On 3/15/2020 9:47 PM, Mike Wilhelm via AMSAT-BB wrote:
Stumbled on this paper by accident:
http://adsabs.harvard.edu/full/1998ESASP.416..715C
-Mike
On Sat, Mar 14, 2020, 10:02 PM Jerry Buxton via AMSAT-BB [email protected] wrote:
Amen.
Jerry Buxton, NØJY
On 3/14/2020 11:53, Robert Bruninga via AMSAT-BB wrote:
We have used NiCds on all of my 4 satellites with no battery problems.
They are robust, and survive all student mistakes and require no Battery management system when paired with a matching solar panel design. IE, as th batteries approach full charge is the same point where the solar panel voltage maxes. Also NiCd's can be safely overcharged at 10% indefinitely with no concern. (you only get an hour in the sun and then 35 minutes eclipse)...
Yes, they are twice as heavy as Lithium, but the advantages FAR outweigh the criticality of Lithium concerns and complexity of the BMS and total failure on overcharge or undercharge.
And MASS is an advantage! PSAT and BRICSAT-1 are identical 1.5U
cubesats
launched at the same time in May 2015. But PSAT with big C cell NiCd's
was
made heavier with lead ballast to 2.3kg. BRICSAT (1.7 kg) with
lightweight
Lithiums has already decayed in November. PSAT is predicted to last 2
more
years! Same thing for identical RAFT and MARSCOM cubesats back in 2006. RAFT was ballasted up and lasted TWICE as long as MARSCOM.
For comm satellites, there is no reason to come in under mass. Always ballast up to the maximum the launcher will allow!
Bob, WB4APR
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
participants (6)
-
Diane Bruce -
Jerry Buxton -
Jim White -
Mike Wilhelm -
Pedro Converso -
Robert Bruninga