Battery Charger

[quendi]

are there any plans to make a stand alone charger for the battery? so you can use your pandora on the road while your second battery recharges at home?

 

[eksasol]

*snip*

 

[Chip]

The battery is not removable, it is but not with sliding and snapping style like labtop. I think it uses a little connector that connect two pins like any other standard internal li-on batteries.
Only the dev boards were set up like that. You can see a pic of the production battery here: CODE
i198.photobucket.com/albums/aa99/MWeston_2007/production_battery.jpg

Those contacts line up with three springy contacts on the Pandora, so it is easily removable.

There are no plans at this time to build a standalone battery charger, but it might be considered as a future accessory.

 

[CCmachined]

The battery is not removable, it is but not with sliding and snapping style like labtop. I think it uses a little connector that connect two pins like any other standard internal li-on batteries.
Only the dev boards were set up like that. You can see a pic of the production battery here: CODE
i198.photobucket.com/albums/aa99/MWeston_2007/production_battery.jpg

Those contacts line up with three springy contacts on the Pandora, so it is easily removable.

There are no plans at this time to build a standalone battery charger, but it might be considered as a future accessory.


Would it be as simple as a regulated voltage of 5V in series with the pack or similiar? (since thats the charge input voltage)

 

[pelrun]

Would it be as simple as a regulated voltage of 5V in series with the pack or similiar? (since thats the charge input voltage)

NO. Never, *ever* try this with a Li-Ion battery, you will get an large explosion and fire.

Only use chargers explicitly designed to charge Li-Ion batteries, as they can deal with the complicated charging method required. At the very least, 5v is way above the Li-Ion maximum charging voltage - just because the Pandora takes 5V does not mean the battery does!

 

[Chip]

Would it be as simple as a regulated voltage of 5V in series with the pack or similiar? (since thats the charge input voltage)
NO. Never, *ever* try this with a Li-Ion battery, you will get an large explosion and fire. This is correct. Using anything other than a charger specifically designed for your battery is seriously dangerous. Li-Ion chargers a much more complex and constantly monitor the battery's condition to prevent over charging and explosion. This is not something you can safely build yourself.

Here is what happens when you overcharge a LiPo battery: youtube.com/watch?v=lCFUGDcSuLw

 

[christo930]

Would it be as simple as a regulated voltage of 5V in series with the pack or similiar? (since thats the charge input voltage)
NO. Never, *ever* try this with a Li-Ion battery, you will get an large explosion and fire. This is correct. Using anything other than a charger specifically designed for your battery is seriously dangerous. Li-Ion chargers a much more complex and constantly monitor the battery's condition to prevent over charging and explosion. This is not something you can safely build yourself.

Here is what happens when you overcharge a LiPo battery: youtube.com/watch?v=lCFUGDcSuLw

The worst part about the danger of lithium polymer batteries is that many of them are made for children's devices which often can take much abuse. In general they are safe, but they can catch fire from over discharging or overcharging (overcharging is MUCH more likely to cause a fire than high discharge). But imagine a battery shorting somehow on a device in a 10yo's pocket. Scary.

Chris

 

[Mithrildor]

Will the pandora have a system to prevent the burning of the battery? So that it wont burn when I leave the charging on in the night (or is that a stupid idea)

 

[pelrun]

Of course - it's just like any laptop/netbook in that regard. They'd have a hard time getting a device which exploded overnight through testing

 

[CCmachined]

Would it be as simple as a regulated voltage of 5V in series with the pack or similiar? (since thats the charge input voltage)

NO. Never, *ever* try this with a Li-Ion battery, you will get an large explosion and fire.

Only use chargers explicitly designed to charge Li-Ion batteries, as they can deal with the complicated charging method required. At the very least, 5v is way above the Li-Ion maximum charging voltage - just because the Pandora takes 5V does not mean the battery does!

I see i see. I was thinking about the way lead acid batteries charge by a slightly higher voltage.

Is the battery a standard unit of some kind(compatible with other devices / chargers) or specifically designed for the pandora?

 

[Chip]

Is the battery a standard unit of some kind(compatible with other devices / chargers) or specifically designed for the pandora?
It is designed for the Pandora. About the only thing that could safely charge these batteries (other than the Pandora itself) is a LiPo universal smart charger like this: www.rcaccessory.com/index.asp?PageAction=VIEWPROD&ProdID=311

You would also need to fashion a cradle to hold the battery with contacts in the right place, and it's still possible to cause serious damage if you set the charger up wrong, but it could possibly work.

I do not recommend you attempt this unless you have significant experience with LiPo batteries and their proper handling.

 

[MWeston]

Will the pandora have a system to prevent the burning of the battery? So that it wont burn when I leave the charging on in the night (or is that a stupid idea)

The battery has protection circuits on board to prevent overvoltage, undervoltage, short circuits and general over current situations. The software running on the Pandora will control the charge current to the battery and taper it off as the battery fills. There is a hardware limit to how much current can go into the battery even if the software screws up and I have charged some batteries that way already and the battery doesn't even get warm at full current. The charging circuit on the Pandora PCB does warm up though.

 

[hobbyman II]

do NOT try to fashion your own charger

I use LiPo batteries for my model aircraft (with very high capacities), you could weld a car with some of them and stay inside their safe working range, they contain that much energy, the nasty thing about LiPo fires is they are an oxidiser fire, that means they burn underwater, can`t be smothered or put out by extinguishers and if it goes up indoors you have toxic smoke to deal with as well.

the only approved safe way to discard them is to place them in a bucket/bowl of salted water for a couple of days and then mark them "fully discharged", before handing them in to a reclaim company.

I personally store them in ceramic jars, stacked 2" apart, in a steel box (old ammo trunk) in a section of the garage that is cleared of surrounding combustibles, there was a guy at one event accidentaly mis-set his charger, put a flight pack on to charge and totaly burnt out his car

follow the makers instructions, use the correct specified charger, and all will be well, I have never had issues with any of the gear or packs I use, but then I always make sure I use the right gear, even my adaptors/chargers are labeled at the plug and the connector end, theres a reason they put all those warnings in manuals

 

[CCmachined]

Deceivably small lithium batteries can actually jump start a car:

http://www.youtube.com/watch?v=1w_K08fwZnA...re=channel_page

Imagine all that power in an explosion with additional energy from the battery chemistry...

 

[pelrun]

If you get spare batteries you're going to have to be very careful with them, as they don't appear to have solid cases like most Li-Ion packs do (although I do hope I'm mistaken...)

That means keeping them where they won't get sat on, crushed, punctured etc - don't just drop one into your bag! Even slight damage to a Li-Ion cell can cause an internal short circuit, leading directly to the same unstoppable explosion and fire as previously mentioned.

 

[Monk]

Soo...if we can't use standard power supplies to charge spare batteries, what use are they really? Apart from as bombs? Are they unreliable enough that a second one makes any sense at all if you need the Pandora to charge it?

 

[WizardStan]

Just to intercede on what you seem to be implying: there is nothing inherently dangerous about the Pandora batteries specifically. The exact same danger exists with standard rechargeable Lithium batteries. Charging a AA Lithium battery in a charger meant for a NiMH (or even worse, the old Alkaline) will cause heat, possibly rupture and eventual explosion.

To answer your question, though, it's easy to swap batteries out, so there's no reason you can't charge one up the day before a big trip, charge the other overnight, and then take both with you wherever you're going. If you want an always-ready spare, fully charge the second and stick it in an airtight bag in the freezer. Unless you intend to have 24 hours gaming sessions, you can easily work around the problem of not being able to charge the battery separately.
Although I'm sure, given a bit of time, someone will figure out a safe charging station. OP may even sell such a thing eventually, though I wouldn't hold my breath.

 

[Tor]

I would put it in the fridge, not the freezer..

 

[JayFoxRox]

pelrun: www.gp2x.de/images/temp/protobatt.jpg
this looks like it is solid, on the sides around the core, but I wouldn't stomp on it too and would feel alot safer with a real case around it.
//Edit:ed to make sense

 

[pelrun]

The exact same danger exists with standard rechargeable Lithium batteries. Charging a AA Lithium battery in a charger meant for a NiMH (or even worse, the old Alkaline) will cause heat, possibly rupture and eventual explosion.

You're confusing chemistries - AA lithium cells are lithium iron disulphide, not rechargeable, and nowhere near as dangerous as Li-Ion.

You don't see Li-Ion in the consumer market for two reasons - the safety aspects, and the fact that the cell is 3.7v and therefore incompatible with AA's ~1.5v.