Talk:Neo FreeRunner Battery
It would be good to add information on what brand/model numbers can be used here.
I'm not sure it it solves a 'deep discharge' problem. I noticed that if the power from USB is not sufficient to boot Linux it is sufficient to log into NOR. Than if I discharged OM: 1. Connect the USB connector 2. OM would try to boot but kernel panic will occure due to insufficient battery (flashing red light) 3. I can turn off the phone and switch it on logging into NOR (I have to check if I can skip to this step by holding AUX) 4. Then I wait a while and choose to boot OM
Do we have any updates on the replacement battery table? are there any batteries that correctly show charging information?
Larger case + rechargable AA(A) or 3,7V Lithium
//17SEP09 UPDATE: Found a 3d case file, see "making it fit" below
Hello, I am using the Freerunner for about a week now, and it's a neat device :-) While the original batteries are not that expensive, and DX offers low capacity BL-5C batteries for less then $3, I would really like to be able to use regular rechargable batteries.
//17SEP09 UPDATE: With a larger case and 4-5 3.7V/2500mAh (18mm diameter) would be great for geocaching
If I am on the go, I can just use cheap batteries or rechargables instead of relying on the small Lithiumbattery or running arround with spares.
While external batery supplies are easy to build and could just be attached to the USB port, this is not very efficient. I'dd rather have a teather-free device and have the batteries supply the freerunner directly (even if it could not charge them).
As it seems even AAA ("Micro"/HR03/LR03) can hold up to 1000mAh these days (NiMH rechargeables). http://www.chip.de/artikel/Megatest-Akkus-fuer-Digicams-und-MP3-Player-AA-AAA-6_29020761.html (german). 1000mAh is pretty close to the original batteries 1200mAh.
//17SEP09 UPDATE: 3.7V 2500mAh batteries cost arround $4-$5 Each at Dealextreme, some have a over/undercharge protection built in
What is the lowest voltage the freerunner will be able to run on? NiMH-rechargables will provide 1,2V relative constantly; http://img.photobucket.com/albums/v482/SilverFoxCPF/EneloopAA2000atVariousRates.gif As most tests I found where doing 200mA discharges or so, that should be okey (right now my FR uses arround that with 50% display brightness, no GSM but GPS; With active GPRS and bright display it can jump up to 400-500mA which could be a problem on cheap AAAs)
As the phonebatteries are rated with 3.7 Volt, the battery status showing 3,6 - 3.8V. Three full (1.25v) NiMH batteries will provide 3.75V; 3*1.2V->3.6V, so full batteries would provide sufficient power. How about almost discharged batteries (3.3V, 3V...) or regular one-use batteries (up to 4.5V or more when full, and under 3V when discharged)?
//17SEP09 UPDATE: Lithium-Cells would just "pop in", but I'dd charge them seperatly
Making it fit
Unfortunaly, three AAA batteries will fit into the battery slot but are slightly thicker then the batterypack, and the lid will not shut. Their diameter is a bit more then 1 cm depending on the brand, the ones I have laying arround have 11mm (=3/7th of an inch), while the battery is 7mm...
//17SEP09 UPDATE: Lithiumbatteries/rechargables have a 18mm diameter.
So what are the options?
Modyfying the existing case mechanically or with heat (ugly) or working on a case that is just slightly larger... One of the 3D rapid prototyping services (Shapeways or rapidobject.com) that produce low quantities or single items for about $2-$4 for a cubic centimeter of material. (I saw more services listed on http://wiki.openmoko.org/wiki/Hardware:Neo1973:Alternate_Cases)
The only things I could find so far was http://wiki.openmoko.org/wiki/Wishlist/Expansion_Back and external battery supplies.
Sorry for the long ramble. I'dd apreceate any feedback... Thanks :-)
--Schorhr 19:09, 9 September 2009 (UTC)