wow … an 18650 with a real capacity of more then 3100 mAh
(discharged for > 3 hours @ 1 Ah to 3V)
one of the best i’ve seen : panasonic NCR 18650B (used in el. cigarettes)
- warning - these batteries are unprotected
wow … an 18650 with a real capacity of more then 3100 mAh
(discharged for > 3 hours @ 1 Ah to 3V)
one of the best i’ve seen : panasonic NCR 18650B (used in el. cigarettes)
Guys,
I mounted R-Divider breakout board, time to get some code working, but ready to measure from any 3.3V CPU with I2C and no descent Analog input, ohh, did I say ESP8266 ?
Here are picture, as you can see, seems PCBs.io silk is much better now, really close to OSHPark
Assembled
I’ve just put 1% 1M+1M Resistors and 100nF filtering, so we divide input voltage by 2 (so up to 6.6V input)
Assembled and stacked with ADS1115
@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.