LastAMP

thingiverse

A clever device for extracting nearly all energy from a seemingly lifeless AA battery. Sales data from leading manufacturers reveal that in 2016 alone, enough AA batteries were sold to equip every American with 10 batteries each. The most widely used battery type in US households is the AA-sized "penlight" battery. In Britain, this battery is often referred to as an HP7. The International Electrotechnical Commission designates non-rechargeable AA batteries as R6 & LR6, while the American National Standards Institute defines them as size type 15 (e.g., 15D & 15A). When discarded, a "dead" AA alkaline battery may still hold 0.8-1.33V of usable energy, according to Linden's Handbook of Batteries. In fact, batteries removed from toothbrushes used in testing had 1.33V remaining, demonstrating the potential for reuse. This device is inspired by Big Clive's "joule thief" circuit, which can be found at http://www.bigclive.com/joule.htm. The LAMP circuit utilizes a tilt switch to harness energy from the presumed dead AA battery and power an LED. Required components include: * 1x - 1/4 watt 5% resistors (200 pieces, BG Part Number: RES1136, $3.66) * 1x - Toroid cores (#6 mix(yellow), BG Part Number: COL1058, $1.10) * 1x - 2N3904 NPN TO-92 40V (100 pieces, BG Part Number: TRN2N3904, $6.00) At Mouser: * 1x - 611-RB-231X2 C&K Components Tilt Switches ROLLING BALL RB-231X2 ($1.12) * OR, 611-RB-220-07AR C&K Components Tilt Switches ROLLING BALL RB-220-07A R ($1.00) * OR, 612-TM1000Q E-Switch Tilt Switches 20mA 20VDCTM1000Q ($1.54) Also needed: * 1x - 604-WP7113LSECKJ4 Kingbright 5MM LOW CURRENT ORANGE LED WP7113 ($0.49) * OR, 859-LTL2R3FU3JSR Lite-On Amber 604nm Clear 5mm LTL2R3FU3JSR ($0.20) * OR, 604-WP483EDT Kingbright Orange 625nm Diffused 7mcd WP483EDT ($0.18) Additionally: * 1x - 12BH311P-GR Eagle Plastic Devices Holders 1 "AA" PC LEADS BLK ($0.97) * Two pieces of different colored thin 24 gauge wire (or thinner) about 13-inches long each, wrapped around the toroid. To assemble, wrap two wires together and then around the toroid. Join two opposite wires and solder them to the red connection from the AA battery holder. Before threading the lid onto the base, apply household bar soap to the threads. If stuck, use a wrench to "coax" the lid off. Remember to reduce, reuse, and recycle!