Li-ion

31 Articles

Laptop Running On A Sealed Lead Acid Battery

September 20, 2009 by 24 Comments

steupup_box

[Viktor’s] laptop needed a new battery; he had the trade off between carrying around a cheap but heavy sealed lead acid (SLA) battery, or buying an expensive but light Li-Ion battery. Figuring his old laptop was pretty heavy already, and having an unused SLA available, re-purposing it for his laptop wouldn’t be too much of a hassle. Using a boost converter he built out of a custom dip MAX668, he is able to output the necessary 5 amps required. An MC 34161 voltage monitor chip is planned for future revisions, but he’s currently running it just fine. Check out some of his other cool hacks on Karosium.

Related: MSI Wind extended battery

Adjustable Breadboard Supply

July 16, 2009 by 12 Comments

breadboardpowersupply

adafruit industries’ latest product is an adjustable breadboard power supply kit. We’ve seen breadboard supplies before, but like most of adafruit’s kits, this is the best design you’re going to encounter. It uses an MIC2941 voltage regulator instead of the more commonplace LM317. It has a very low dropout which means your output voltage can be much closer to the input voltage. Their example is using 3AAA or a Li-Ion battery for an output of 3.3V. Input can be through a barrel jack or terminal blocks. There is a selection switch for 3.3, 5, and adjustable voltage. Using the adjustment pot you can select an output voltage anywhere from 1.3V to within .5V of the 20V maximum input. The adjusted output voltage will remain the same even if you increase the input voltage. Like all of their kits, you can find schematics, assembly and usage instructions, on their project site.

Unique Li-Ion Battery Tester

May 15, 2009 by 16 Comments

battery

[moris_zen] found himself with a hand full of Li-Ion batteries and no good way to see what their capacities were. He built a this unique tester really quick to get the job done. He’s using off the shelf components and a cheap pocket watch which he bought in Taiwan for $1. You hook the circuit up to your battery, click the button and the watch starts working. When it stops, you multiply that number by .38 to get your amp/hour results. Sure, he could have just used a counter, but this is an interesting approach. All he needs to do now is make a nice container to hide all of the circuitry. How could he change the circuit to make the end multiplication unnecessary?