{"id":3610,"date":"2012-05-17T10:08:43","date_gmt":"2012-05-17T08:08:43","guid":{"rendered":"http:\/\/www.gsm-modem.de\/M2M\/?p=3610"},"modified":"2012-05-17T10:08:43","modified_gmt":"2012-05-17T08:08:43","slug":"gsm-phone-15-years-on-a-single-charge-of-an-aa-battery","status":"publish","type":"post","link":"http:\/\/www.gsm-modem.de\/M2M\/m2m-componets\/gsm-phone-15-years-on-a-single-charge-of-an-aa-battery\/","title":{"rendered":"GSM phone – 15 years on a single charge of an AA battery"},"content":{"rendered":"

Not to bad. Link to the description of the phone.
\nhttp:\/\/www.intomobile.com\/2012\/05\/16\/spareone-phone-lasts-15-years-single-aa-battery\/<\/a><\/p>\n

Nevertheless I am working on a 65 gram bird tracker with the target to run endless. Right now Eneloop batteries are in use. Eneloop offers a self-discharge of 25% within 3 years. If the self-discharge is linear, then after 15 years 23,7 % capacity is left. Such a AA cell offers 2400 mAh hours. After 15 years will be still 577 mAh left.
\nThe phone promise 10 hours talk time. 10 hours talk are 5 hours transmit and 5 hours receive? I am not sure. Anyhow a state of the art GSM module discharge the battery with 230 mA during maximum power level of 2 Watt. 2400 mAh \/ 230 mA = 10,41 hours. So after charge the 10 hours are possible and after 15 years we have 577 mAh \/ 230 mA = 2,5 hours transmitting time left.
\nThe AA batteries are public at the link as below. Just calculate yourself.
\nhttp:\/\/www.eneloop.info\/products\/batteries.html<\/a>
\nAnyhow, this phone could run endless too. It just has to use energy harvesting by solar or temperature delta.<\/p>\n