LowPowerLab Forum

Hardware support => Low Power Techniques => Topic started by: gert on May 31, 2017, 11:28:10 PM

Title: Concurrent solar cell / charger / moteino power
Post by: gert on May 31, 2017, 11:28:10 PM
Hello All,

For an autonomous outdoor moteino system I am looking at a solution to combine a solar cell / Lipo battery / charger circuit. The charge controller must be intelligent to swap between charging and load operation. I don't want to unplug/replug things along the way. Also no overcharging of the battery. Just deploy-and-forget. Is there a ready made circuit board / shield to do that? I've seen discussion on the forum but no actual circuit offered.

There is this circuit from another supplier. (although currently out of stock)
https://www.adafruit.com/product/390
Would that work for moteino?

Thanks,
Gert
Title: Re: Concurrent solar cell / charger / moteino power
Post by: sparky on June 01, 2017, 06:29:49 AM
Have you looked at this thread;

https://lowpowerlab.com/forum/projects/a-solar-supercap-powered-moteino/

A lot of time and effort went into this discussion and it has a lot of design circuits.
Title: Re: Concurrent solar cell / charger / moteino power
Post by: i670 on June 01, 2017, 05:04:39 PM
I use these

https://www.dfrobot.com/product-1139.html

dave
Title: Re: Concurrent solar cell / charger / moteino power
Post by: syrinxtech on June 04, 2017, 10:22:23 AM
@gert,

Check out my outdoor weather station in the Project section.  I am doing exactly what you're referring to in your post.  I have a solar panel that charges a LiPo battery using a charging board.  It uses a thermistor that regulates charging when it gets too hot or cold.

It has been outside running for almost a year now totally on it's own.  You can see the output at:

https://freeboard.io/board/5epTjs

Title: Re: Concurrent solar cell / charger / moteino power
Post by: syrinxtech on June 04, 2017, 10:40:44 AM
@gert,

I attached a picture of the components.  The picture shows the original layout in a weatherproof box but since then we moved it to a wooden box with slats which allow for airflow.  The components are the same, just a different housing.

BTW, the charger is from Adafruit, #390.

Title: Re: Concurrent solar cell / charger / moteino power
Post by: TomWS on June 04, 2017, 11:10:32 AM
Quote from: syrinxtech on June 04, 2017, 10:22:23 AM
@gert,

Check out my outdoor weather station in the Project section.  I am doing exactly what you're referring to in your post.  I have a solar panel that charges a LiPo battery using a charging board.  It uses a thermistor that regulates charging when it gets too hot or cold.

It has been outside running for almost a year now totally on it's own.  You can see the output at:

https://freeboard.io/board/5epTjs
Nice!  I like the rolling digits on the numeric updates.  What widgets are you using?  We should move this to another thread if it's going to be a 'conversation'...

Tom
Title: Re: Concurrent solar cell / charger / moteino power
Post by: syrinxtech on June 04, 2017, 01:39:05 PM
@TomWS,

I have a running thread about my unit in the Projects section.  It's one of the "saved" projects so it should be near the top.

By widget do you mean physical sensor, or software component, or both?

The indoor base station Mega receives the outdoor transmission and is serially connected to a Spark Photon.  From there it's a wireless connection to the Internet.  The Photon uses the "publish" feature to upload JSON data to Freeboard, a free tool that I use to visualize the data.

Did that answer your question?
Title: Re: Concurrent solar cell / charger / moteino power
Post by: TomWS on June 04, 2017, 06:59:58 PM
Quote from: syrinxtech on June 04, 2017, 01:39:05 PM
... The Photon uses the "publish" feature to upload JSON data to Freeboard, a free tool that I use to visualize the data.

Did that answer your question?
Yes.  I was interested in what kind of HTML/Javascript gizmo was used to display the numeric data.  On each update the digits 'rolled' to their new value.  Neat behavior.

Thanks,
Tom
Title: Re: Concurrent solar cell / charger / moteino power
Post by: syrinxtech on June 04, 2017, 09:55:58 PM
All the "fanciness" is built into Freeboard.  All I do is "publish" the variables from the Particle Photon and Freeboard reads the variables and has  a number of widgets to display the data.

Here is another view of the same data:

https://freeboard.io/board/MCsvrV

Title: Re: Concurrent solar cell / charger / moteino power
Post by: HeneryH on October 09, 2017, 09:32:33 PM
Anyone running in cold environments?  I'm in an area where winters get down into the single digits or teens Fahrenheit and I've read that the LiPo aren't good in those temps.  There is a while thread about capacitor based solar chargers referenced earlier in this thread but damn, it is over 20 pages of design discussion.  I'm looking for the Cliff Notes version.
Title: Re: Concurrent solar cell / charger / moteino power
Post by: syrinxtech on October 09, 2017, 09:43:14 PM
HeneryH,

My outdoor unit has been running for over a year now.  The high temps here in Va. have gotten as high as 100 and as low as single digits.  So far, everything has been running great on my LiPo.