@BoRRoZ
It’s just a R-Divider (if you already have Analog input on device) and if not (like ESP8266) you can stack it with ADS1115 board (I2C 4 ADC inputs) like below. You can see github readme for more information
You can find this ADS1115 board (new version smaller) on ebay for less than $3
ah ok tnx 
and you know… not all LiPo’s are equal - never believe what’s printed on them
Hey, yeah I know that, how do you find the real value, you count time to fully charged to discharge at specific AMP ?
yes , I have 2 possibillities, the Maynuo M9812 electronic load and the Turnigy Accucell 6
The Maynuo have a special battery testfunction and can, when connected to PC spit out information/graphs
You set the end voltage (normal between 2.75 and 3.2 V depends on the buildin protection circuit/datasheet)
and you set the discharge current (between 0.2 and 1 C)
then push start and go do the dishes/do some shopping and when reached the end voltage it stops discharging and give you the mAh.
what I really need is a logging power tool… like Ladyada
have been busy finding a diy solution
just curious, did you ever measure the cheap ‘action’ 2000mah AA powerbase batteries?
no, have been testing chinese Ultrafires … that’s really crap
oh, and how bad was it? 
More or less like this, he has the same cheap charger/discharger, they work really good !
I mounted it on an old PC power supply
I have a clone I think, anyway, if you connect them with an old PC powersupply you can do many things.
a very nice menu option is ‘storage mode’, the charger checks the lipo and if its full it start discharging to 70%, if its empty it starts charging to 70%.
one thing you must watch:
If you set it to LiPo discharge, it stops (preprogrammed) @ 3.2 V
What I do, i discharge LiPo with NimH selected , there I can set amps and voltage, so I set that to 2.8 V, then I know its really empty.
Then I set it back to LiPo and charge (it stops preprogrammed @ 4.2 v and when the current is < 0.01 A
Now you can read on the display the real capacity.
To spare your battery’s discharge @ 0.2 C and wait 10 minutes between discharging and charging.
always be extra carefull when charging LiPo batteries !
these panels get… hot
I’m experimenting with a solar panel & supercaps.
The start looks promissing, but the main challenge is the power consumption of the LoraWan communication with the 3.3V RN2483.
The delay of the gateways is a problem for me because I live in the center of large white spot on the map in the Netherlands without existing coverage from TTN gateways. But better to wait and receive a solid product. 
In case you want to check or add some suggestions, the URL is:
Best regards,
Peter
nice project Peter … not much sun lately
I received last week some supercaps, small ones 0.47 uF and bigger ones to do some measurements, like on the gammon site
Oh and you should really talk to Charles CH2I … he is THE lowpower low voltage specialist
Still no sun today
I’m also curious how it is going to perform.
In case I need more current it is also possible to use multiple series banks in parallel but then it becomes more complex with balancing resistors in the supercap bank.
Today I tested a RN2483 for connectivity to ensure that is works, and it did! Still had to use the KPN LoraWAN network because there is no TTN gateway in range of my house. I used a terminal session and AT commands to insert the necessary config settings and saved in to the EEPROM of the RN2483. This simplifies the sketch on the Atmega328P.
Three challenges that I’m struggling with:
And don’t know the person you mentioned but every help is welcome.
Best regards,
Peter
this is low power work from Charles CH2I … very interesting
btw I didn’t realize that you need a ‘balancing’ board for supercaps
Looks impressive!
It should be could to first really fully charge them and leave them for a day.
With your 5.5V caps in parallel you don’t need such a balancing system if I correctly understood.
I have similar caps like you ordered but one small disadvantage is that they are not breadboard friendly to experiment with. That is way I now use other ones.
Today the first successful transmissions using the RN2483 and Atmega328P powered by 2 supercaps. 
I am wondering if anyone has experience with the following solar charging modules:
LiPo Rider Pro from SeeedStudio
https://www.seeedstudio.com/LiPo-Rider-Pro-p-992.html
Generic solar charger on ebay:
http://www.ebay.com/itm/5V-Solar-Charger-Receiver-Module-Solar-Controller-3-7V-Lithium-Battery-Charger-/272493130063?hash=item3f71db314f:g:s5gAAOSwUsJYWkod
The LiPo Rider has a only 3 reviews on Amazon, with one indicating the board does not work as advertised.
Any comment is appreciated.
Hi,
for those of you with more electrical engineering experience, would a goldcap or a super capacitor be a good choice to power a LoPy in the field, if it gets additionally supported by a solar cell?
Just thinking about what is better in terms of long live…
https://www.reichelt.de/Speicher-Elkos/2/index.html?ACTION=2&LA=3&GROUPID=3148
As a solar cell, this one may be more than capable for such an application:
https://www.wattgeizer.com/et-solar-et-m53605-5-wp-solarmodul-monokristallin-12v?c=36
The LoPy is only an example. It’s more about the type or class of device (low power device) and the powering options for really long periods without having to worry about charging cycles of a normal rechargeable battery.
Lothar
I’m no electronics expert but would suggest a lower voltage solar panel and look for the amount of current it can supply under normal conditions.
If you standardize for lower voltage mcu & lora module like 3.3v and use simple components to lower voltage like a LDO than avoid a 12V panel because the voltage difference is largely wasted as heat.
If I’m correct then gold-cap is a brand name that also supplies supercaps.
Knowing if it fits depends on usage & sleep scenario, energy consumption of mcu & lora module, etc. This determines the needs for power supply.
I’m expertimenting & learning with something similar, project is now “on hold” till some components (328PB and RN2483A) arrive in June.
@lollisoft In normal situations you’ll not have to worry about wearing out your battery, either LiPo or NiMH.
I’ve been running small solar powered NiMH projects for many years and the cells are still in excellent condition. The main issue is surviving the dark winter months (december and january). A Super capacitor has in many situations insufficient capacity for these dark months.
You could use a very large panel so that it would fully charge the supercap even on a very dark overcast winter day. That would work and would get you through the night, but the solar panel and super cap size and costs are probably much higher than a smaller solar cell combined with (a) chemical rechargeable cell(s).