{"id":182,"date":"2019-04-07T18:11:12","date_gmt":"2019-04-07T08:41:12","guid":{"rendered":"https:\/\/sighmon.com\/says\/?p=182"},"modified":"2019-04-07T18:16:22","modified_gmt":"2019-04-07T08:46:22","slug":"power-battery-management","status":"publish","type":"post","link":"https:\/\/sighmon.com\/says\/power-battery-management\/","title":{"rendered":"Power & battery management"},"content":{"rendered":"\n

Until now I’ve been powering the water quality sensors via a USB cable either to an external power supply, or directly to my laptop for debugging.<\/p>\n\n\n\n

For the sensors to work in the real world they’ll need to have at least a day’s battery life if not a week to be useable. I can imagine going for a walk every weekend to replace rechargeable batteries would be fine, but any shorter than that might get a bit tedious.<\/p>\n\n\n\n

I have a few friends in the mobile phone repair business, and they gave me a supply of phone batteries that were past their prime for supplying high amp outputs, but seem to be fine for a regular trickle like this project. So I’m hoping that maybe I can make use of a bunch of those 3.7v 1050mAh batteries and give them a new life.<\/p>\n\n\n\n

To get their 3.7v up to 5v that The Things Uno uses, I’ll need a boost converter – so have been playing with this Adafruit 1000c<\/a>.<\/p>\n\n\n\n

\"\"
Adafruit 1000C boost converter & recycled Nokia 3.7v 1050mAh battery.<\/figcaption><\/figure>\n\n\n\n

This setup works very nicely, but given that these batteries are quite old I’d expect to only get about 85% of their original capacity from them. So let’s do a little test.<\/p>\n\n\n\n

\"\"
Battery life calculations.<\/figcaption><\/figure>\n\n\n\n

To my utter surprise, I actually got ~5 hours out of the old Nokia battery or about 90% of it’s original life. And that’s including the boost converter efficiency loss too. So things are looking good.<\/p>\n\n\n\n

Clearly 5 hours is not equal to 1 week. So next I’ll have to go back to the Arduino code, and perhaps only measure once a minute instead of once a second, and see if I can get it to sleep in between to save battery life. 🤞🏼<\/p>\n\n\n\n

But in the meantime, it’s nice to see it all fit in the water-proof case<\/a>, and transmit for 5 hours without a problem!<\/p>\n\n\n\n

\"\"
All of the components fit snugly in this water-proof enclosure.<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"

Until now I’ve been powering the water quality sensors via a USB cable either to an external power supply, or directly to my laptop for debugging. For the sensors to work in the real world they’ll need to have at least a day’s battery life if not a week to be useable. I can imagine … <\/p>\n

Continue reading “Power & battery management”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":186,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[40,11,35,39,37,38,36,14,34],"class_list":["post-182","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-adafruit","tag-arduino","tag-battery","tag-boost","tag-mobile-phone","tag-nokia","tag-recycled","tag-sensors","tag-water-quality","entry"],"_links":{"self":[{"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/posts\/182","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/comments?post=182"}],"version-history":[{"count":1,"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/posts\/182\/revisions"}],"predecessor-version":[{"id":187,"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/posts\/182\/revisions\/187"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/media\/186"}],"wp:attachment":[{"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/media?parent=182"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/categories?post=182"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sighmon.com\/says\/wp-json\/wp\/v2\/tags?post=182"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}