Topic: Ultra small back-up batteries

[Jeffy]

Anyone use anything like these?  I've seen a few pop up and they're really interesting, especially with the compact size.

[sharpxmen]

so that's to jump the car if the battery is low? (and you charge it from your cellphone?) I can't see why it would have the clams otherwise and not the lighter plug.

[Jeffy]

so that's to jump the car if the battery is low? (and you charge it from your cellphone?) I can't see why it would have the clams otherwise and not the lighter plug.

No, you can use it to recharge your phone as well as jump your car battery.  I'd imagine it has a USB to A/C adapter cable.

[sharpxmen]

No, you can use it to recharge your phone as well as jump your car battery.  I'd imagine it has a USB to A/C adapter cable.

if it's 12v you won't be able to charge it from a USB 5v DC source (at least not without some additional hardware), makes no sense to do a step-down and then use some commutating power supply to get 12v.

[Jeffy]

Here's another one by Cobra.

https://www.cobra.com/products/portable-power/cobra-jumpack%E2%84%A2

Jump start your car and charge your mobile devices - Multiple times
200 Amp Starting Current, 400 Amp Peak Current -  Jump starts most cars.
2.1 Amp USB Port for Rapid Charging of Portable Devices - Quickly charge your cell phone, smartphone, tablets and other mobile devices.
Built-in LED Flashlight - Super-bright work, strobe and S.O.S. Emergency LED light.
7500mAh Lithium-Cobalt Battery - Holds a charge longer and is smaller than traditional jumpstarters.

Supposedly it will hold a charge for a year.

[neale_rs]

Pretty amazing battery technology.

[jfrabat]

Had not seen these before.  But, after seeing how some of these batteries hold up, I am not sure I would like one more thing that can catch fire inside the Jeep (I have heard about some large capacity USB backup batteries catching fire around here).  Otherwise, this is a nice idea!

[Jeffy]

Had not seen these before.  But, after seeing how some of these batteries hold up, I am not sure I would like one more thing that can catch fire inside the Jeep (I have heard about some large capacity USB backup batteries catching fire around here).  Otherwise, this is a nice idea!

Well, think of it this way.  Do you have a cellphone or a laptop?  Has it caught fire?  Those fires were from lithium-ion batteries and were caused by defects in the mfg. process.  Typically when a short happens the battery will get warm and puff up.  If you're charging it it may puff up and breach the plastic casing and release lithium sparks.  The other battery that's come under scrutiny is the Lithium Polymer or LiPo.  Though the same issues that plagued the early Li-ions happened with the LiPo's.

This is a different type of battery.  LiCoPo's and LiFePO 4's, they're supposed to be a bit safer.

The one thing that LiCoPo's. LiFePo's and LiPo's can do that other batteries can't is release a lot of amps at once.  I have some bare LiPo's and basicaly it's just shrink wrap between the bundles of rolled up sections, no hard case.  This is pretty standard for R/C applications.

I believe all LiCoPo, LiFePo and LiPo are made in China.

Here's a video of the process from the US company Revolectrix who make a really nice charger.

<a href="https://www.youtube.com/v/dmwxk5boIrw" target="_blank" rel="noopener noreferrer" class="bbc_link bbc_flash_disabled new_win">https://www.youtube.com/v/dmwxk5boIrw</a>

Here's another by Orion.  Has an added safety, they mount their batteries in a plastic case for R/C buggies.

<a href="https://www.youtube.com/v/6vBH6zlrXuM" target="_blank" rel="noopener noreferrer" class="bbc_link bbc_flash_disabled new_win">https://www.youtube.com/v/6vBH6zlrXuM</a>

[Da_Skunk]

I wanted dual batteries for my jeep, you know a backup or for winching when I couldn't have the motor running. So to save some space I put in a motorcycle battery

[Jeffy]

I wanted dual batteries for my jeep, you know a backup or for winching when I couldn't have the motor running. So to save some space I put in a motorcycle battery

A motorcycle batter isn't going to help for winching.  At best you can use it to jump your battery when it's dead.

These batteries that I'm talking about are ultra small jump starter batteries that can be used for other things as well.  It's small enough that you could carry it in your pocket.

[sharpxmen]

the ones that caught fire recently if i recall correctly were a version of LiFePo with some Manganese in them, apparently they have higher capacity or smaller size for the same AH and can sustain lot higher discharge and recharge currents but are more prone to catching on fire, something i read or seen somewhere not first hand info so could be wrong (can't remember if this was the Boeing issue or something else like an EV or something).

[Jeffy]

the ones that caught fire recently if i recall correctly were a version of LiFePo with some Manganese in them, apparently they have higher capacity or smaller size for the same AH and can sustain lot higher discharge and recharge currents but are more prone to catching on fire, something i read or seen somewhere not first hand info so could be wrong (can't remember if this was the Boeing issue or something else like an EV or something).

Lithium-Ion is the the family name.  LiFePo's don't have manganese in them. LiMn2O4 (Lithium Manganate) and LiFePo's (Lithium iron phosphate) are safer.  Boeing used lithium cobalt oxide (LiCoO2) in the 787's which had problems.  They switched to the LiMn2O4, IIRC.

[sharpxmen]

Lithium-Ion is the the family name.  LiFePo's don't have manganese in them. LiMn2O4 (Lithium Manganate) and LiFePo's (Lithium iron phosphate) are safer.  Boeing used lithium cobalt oxide (LiCoO2) in the 787's which had problems.  They switched to the LiMn2O4, IIRC.

the ones i was referring to contain both Iron and Mn (Lithium Manganese Iron Phosphate cathode material), the batteries without Mn are safer, harder to ignite when overcharching/overloading but at the expense of capacity and discharge/recharge currents.
http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_08dd/0901b803808ddc60.pdf?filepath=dowpod/pdfs/noreg/891-00022.pdf&fromPage=GetDoc
http://en.wikipedia.org/wiki/Manganese(II)_phosphate#Applications

[Jeffy]

the ones i was referring to contain both Iron and Mn (Lithium Manganese Iron Phosphate cathode material), the batteries without Mn are safer, harder to ignite when overcharching/overloading but at the expense of capacity and discharge/recharge currents.
http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_08dd/0901b803808ddc60.pdf?filepath=dowpod/pdfs/noreg/891-00022.pdf&fromPage=GetDoc
http://en.wikipedia.org/wiki/Manganese(II)_phosphate#Applications

But what's the connection to fires?  Boeing's using a different battery all together.  Tesla uses LiCoO2, from what I gather as well.

Also, these booster packs are using a lot fewer cells.  It's no more likely to catch fire then your cellphone.

[sharpxmen]

But what's the connection to fires?  Boeing's using a different battery all together.  Tesla uses LiCoO2, from what I gather as well.

Also, these booster packs are using a lot fewer cells.  It's no more likely to catch fire then your cellphone.

i think just the Mn as it aids combustion, no relation to the small battery posted here -  i just joined the discussion about the batteries catching fire.