At a conference in Germany, engineers unveiled a robotic jellyfish designed to swim—but not sting—like the real thing.

The AquaJelly runs on rechargeable lithium-ion batteries, has a roughly spherical body and uses eight tentacles to get around in the water. The tentacles undulate like the tail of a real fish, and small fins at the ends give the machine a little extra push on the water. To steer, the robot shifts its weight, and it drives around its tank autonomously.

Stanford researchers have figured out a way to incorporate silicon nanowires into rechargeable lithium ion batteries and extend their life from 4 to 40 hours. The work, described in a paper in Nature Nanotechnology, could lead to iPods, laptops and camcorders that could be run nearly for an entire weekend without requiring a re-charge. Of course, this is still in the lab stage, and there are undoubtedly quite a few steps and hurdles between the campus and commercialization, but we're optimists. So, here's to the end of the ABC (Always Be Charging) Rule of electronics.—Gregory Mone

Via News.com

Those hard-working folks at Spark Fun Electronics have taken a good thing and made it better. By taking three of their 2000mAh 3.7V polymer lithium ion batteries and wrapping them up together, they have created a 6Ah powerhouse battery pack (#PRT-08484; $39.95). This is a parallel battery circuit. Also, rather than having to contend with those pesky solder tabs that are inherent to most LiPoly batteries, this Spark Fun power pack is terminated in a convenient JST connector. Oh, and if you don’t like JST connectors, just snip the connector off and solder on your preferred connector.

LiPoly batteries are very picky about recharging. If you’re looking for a suitable LiPoly battery recharger, Spark Fun has an easy-to-use fast charger (#PRT-08293; $19.95). This little black box charger requires a 5V regulated input with a barrel tip. The charger’s output is accessed via a 2-pin screw terminal block. —Dave Prochnow

(Images: Spark Fun Electronics)

If you’re looking for a method to beat battery weight or add some big volts in a tiny space, try experimenting with polymer lithium ion batteries. Better known as LiPoly, lipo, and LipIon, these batteries are very small and lightweight, but they can deliver 3.7V @ 100mAh.

Be forewarned, however, LiPoly batteries require some special handling. For example, only a special polymer lithium battery charger circuit can be used for charging these batteries. Also, soldering the battery’s positive and negative terminal tabs to your project board can be very challenging. Do not exceed a 350F soldering iron temp and work swiftly; using a soldering time of less than 5 seconds.

You can purchase LiPoly batteries from Spark Fun Electronics. A single 100mAh batteries costs around $7.

(Image: Spark Fun Electronics)

Exploring the intricacies of Martian geology requires a steady climber, nimble enough to scale cliffs and dexterous enough to sample the strata. A climbing primate would be a good candidate, if only there were air to breathe and the temperature were warmer than -140

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Dept.: Void Your Warranty

Investigators: Casey and Van Neistat

Personal tech: iPod

Cost: $50 to $100

Time: ~2 hours