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Old 10th June 2013, 06:25 AM   #11
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Quote:
Originally Posted by FoMoCo View Post
I must disagree. However, that sort of flame war is off topic, as the OP has already decided on a different battery technology. Being that as the case, I won't argue pros and cons of battery technologies. Things get out of hand pretty fast here.
You can disagree all you want. Fact is that li-ion batteries not in a device are banned from air transport in any shape or form. Consumers cannot legally buy such batteries anymore if the battery is in another country (for the EU that also means no crossing country borders within the EU). And most shipping companies either refuse to transport li-ion batteries entirely, or charge huge insurance premiums.

li-ion batteries are now considered a hazardous substance.
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Old 10th June 2013, 10:31 AM   #12
FoMoCo is offline FoMoCo  United States
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I disagree as much as you agree.

What puzzles me is the banning outside a device. That's ludicrous. How does being in a device make the battery safer? While it may be a fact, it's not proof of these things being a bomb waiting to explode.
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Old 10th June 2013, 10:54 AM   #13
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Obviously because a battery in a "device" only takes up a certain amount of volume, and therefore the density of hazardous material per volume is significantly reduced. Furthermore, a "device" is typically packaged for shipping drastically reducing the hazardous material per volumes.

Before, batteries were packed tightly in packages and palleted. Which was then stacked inside shipping containers.

Here's how a container ship looks after a li-ion battery container explosion.

Click the image to open in full size.

Click the image to open in full size.
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Old 10th June 2013, 10:59 AM   #14
FoMoCo is offline FoMoCo  United States
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Oil and gasoline can do the exact same thing... Yet... We don't think twice about it... You can show all the pictures you want, and I can argue relative risk all I want. In the end neither of our opinions will change. It'll only just trash up this thread needlessly.
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Old 10th June 2013, 11:44 AM   #15
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What about the just using SLA. Yes they are a bit big and heavy but fairly easy to charge and quite cheap at about $25 for 7.2 A/hr battery.

You can also try a stack of Lithium Polymer batteries and a bunch of charger chips like
Microchip MCP73831 which are about $0.80 each.
Fast Multi-Cell Charger | Multi-Cell LiPo Charging | Adafruit Learning System
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Old 10th June 2013, 07:58 PM   #16
ATAUDIO is offline ATAUDIO  Austria
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I belive the thread Opener said he needs a lightweight boombox.

So SLA I believe is really overkill- My thoughts (and my experiments) are that until about 4 Ah Ni-Mh is the most convenient and straightforward. After that, Li-Fe (With integrated BMS) takes place.
In this particular case, I believe a string of 10 x AA 2100 to 2600 mA/h cells could do the job in half a kilo weight.
Such batteries, if you keep an eye on your supermaket can be found on sale for something like 15 Euro total, good brand ones. Or take a same capacity packaged set for RC models , that would sell for around 30 Euro.
This batteries are rugged, tolerate very deep discharge (that normal SLA really don´t) and can be charged with simple chargers, even DIY ones (just google a little bit around and have fun!)
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Old 11th June 2013, 02:57 AM   #17
rjsaenz is offline rjsaenz  United States
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I don’t want to start an argument with anyone about lithium batteries. Back in 2002 I almost got into the battery business. This is when lithium batteries first started showing up on the market, and started blowing up and starting fires. What kept me from starting that business was the US government started legislation to regulate all commercial lithium batteries. Part of those regulations was to have the batteries tested at altitude. The testing would have cost about $10,000 for every type of cluster of cells with its control circuits and it packaging. The control circuits for a lithium battery control charge and discharge to prevent the batteries from overheating. The packaging for each cluster of cells had to be impact resistant with measures to protect the control circuit from short-circuiting. This is a very simplified explanation. The actual regulations include weight of the lithium metal used and the Wh(Watt Hour) of the fully assembled cells. That being said I have no problems or concerns using and traveling with any commercial lithium battery sold in the US. However I would not use the lithium cells that you see put together by RC hobbyist as these cells with their control circuits likely have not been tested per the IATA regulations which have since been adopted throughout the world. I believe Saturnus is partially correct in saying "Fact is that li-ion batteries not in a device are banned from air transport in any shape or form" This is partially correct. You cannot travel with lithium batteries that are not in a device, or commercially packaged and tested with a control circuit, and impact resistive packaging such as laptop batteries, cell phone batteries, MP3's, commercially enclosed external battery packs, not exceeding 11lbs or 100 wH. This is for carry on. For cargo there is a whole other set of regulations. Sorry for the long explanation.



Here are some of the solutions I have used in a stereo backpack that I have built. I use it skiing and traveling for work and pleasure.



10 AA Rechargeable Batteries I prefer Eneloops
Amazon.com: Battery Holder - 10 Aa: Camera & Photo

Pros: Cheap, batteries can be used in other devices that use AA batteries, works well in extreme weather cold/heat.
Cons: at full volume only 3 ½ hours to 4 hr before you get distortion. You will need 20 AA’s to play about 8 hours at full volume. Pain to charge that many batteries even with quick 15min charger.


10,000mah Lithium Ion battery. Ankar 5v, 9v, 12v external battery
Amazon.com: Anker Astro3 10000mAh Multi-Voltage (5V 9V 12V) Output Portable Power Pack External Battery Charger for iPads, Samsung Tablets, iPhones, Android Smart Phones, Camcoders, Digital Cameras / DV Recorders (Dual USB Output: 5V, 2A; DC Output:


pros: Weight .6 lbs, can charge USB Device mp3, phone. At full volume will last 8+ hours. Can power multiple devices at the same time.
cons: 12v output is regulated to 2A if your device draws more than 2A when powered on the battery shuts off.I got around this by setting the battery to 9v when I turned amp on then slid the switch to 12v. Not good in extreme cold 10 degrees F or colder



18000mah lithium ion Energizer xpal 18000a external battery. 5v, 12v 20v
Amazon.com: Xpal Power XP18000A Energizer External Battery Blk: Cell Phones & Accessories


Pros: weight 1.2lbs, Capacity, will last 2 days. Can power multiple devices at the same time including ipad and computer and t-amp. Can power Topping TP22 which uses 20v or other amps that require more voltage. Has cables and tips for just about any device you might need to charge while traveling.

Cons: Cost 169.00 if you can find it(Always sold out). Make sure to get the xp18000a because the xp18000 cannot charge ipad. Which require 5v 2.1. Not good in extreme cold 10 degrees F or colder


I have never been questioned by TSA while traveling with any of these batteries in my backpack.

Sorry for the long post. I hope someone finds it useful !

Robert
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