{"id":1892,"date":"2016-10-09T19:38:32","date_gmt":"2016-10-09T19:38:32","guid":{"rendered":"https:\/\/ozone.me.uk\/wordpress\/?p=1892"},"modified":"2016-10-09T19:38:32","modified_gmt":"2016-10-09T19:38:32","slug":"powerbank","status":"publish","type":"post","link":"https:\/\/ozone.me.uk\/?p=1892","title":{"rendered":"Powerbank"},"content":{"rendered":"

\"powerbank1\"<\/a> \"powerbank2\"<\/a>Made a powerbank with some lithium batteries so that I can power a Raspberry Pi on a field trip…Currently testing how long it will last under battery power.<\/p>\n

It uses a 4200mah 4cells <\/a>battery, delivering 14.8V to a UBEC 3A 5V converter<\/a>. Should be around 12500mah if there is not too much wasted energy in the conversion etc…if I get 10000mah it will be good enough.<\/p>\n

The 5V current monitoring tool<\/a> is telling me that the Raspberry Pi is consuming approx 250ma per hour.<\/p>\n

So I could hope for around 48 hours of “running”. I am sure that a solar panel will need to be added at some point…again this will need to wait !<\/p>\n

[UPDATE 16th Oct 2016]<\/strong><\/p>\n

I have been running the Raspberry Pi all day with the powerbank. It has been running for approximately 12 hours and the battery is still approx 65% full. I am pleased that the system is working, but it is unlikely that it will run for 48 hours.<\/p>\n

I will try to leave it overnight but I am concerned that I might forget it tomorrow morning and run the batteries flat. Potentially setting a fire ! (Lithium batteries are really scary)<\/p>\n