Experience with N800 portable autonomous battery charger
I've been wondering for a while how to extend the (already quite correct :) battery life on the N800 for long trips without power plug access and planned continuous use. One obvious solution is to buy another BP-5L battery for 40-50 euros (*), but changing the battery means rebooting the N800 and recharging the second battery in parallel means another charger (if the model exists). So I went another route and bought: - 4x AA NIMH batteries with charger (1), - a USB battery extender with room for 4xAA (2) - a USB to N800 power plug adapter, part of a quite complete charger and adapter pack (3) For a grand total of about 50-60 euros. 4xAA batteries output 4*1.2V = 4.8V, not far but below the USB standard 5V so likely to be safe. The mayamax USB adapter says input 5V - output 5.6V 500mA and is a bit bulky so it's not just a cable and probably has some voltage and power control function. I discharged my N800 up to the alert noise (no bar left), then plugged the battery extender plus adapter to the N800 and the N800 started charging right away. In about 4 hours it went back to 4 bars (indication: 4 hours - 6 days with minimum screen brightness so not completely 100% charged since it's 8 hours - 10 days IIRC) then I needed to use the N800 so I removed it from the mobile charger. In theory (see computation below), the 4x AA batteries should be able to charge nearly two times the N800 BP-5L battery, but I've not tested yet this hypothesis. Another thing I'll test is having the N800 at 1 or 2 bars and then pluging the extender and continuing to use the N800 to see if while using+charging the N800 power level goes up, stay the same or go down (say while playing video and testing with different screen brightness levels). If it goes down it means that at some point I'll need to stop using the N800 to get extended battery life. If it stays or goes up it means that you can get all the continuous battery life you want just by carrying the appropriate number of sets of 4x AA batteries (these are quite inexpensive). Exactly what I was looking for :). Did someone else tried something along these lines? Laurent http://guerby.org/blog/ (*) All prices with 19.6% VAT included. (1) 4x 2500 mAh class AA NIMH ~ 10-20 euros often with charger According to tests, this class of AA battery holds around 2.5 Wh, for reference BP-5L is 3.7V * 1500mAh = 5.5 Wh (probably a bit less) http://www.batteryreview.co.uk/battery_reviews/gp_2500_aa.htm (2) ReVolt USB Battery Extender (4x AA) ~ 5 euros http://www.pearl.fr/article-PE4477.html (3) Mayamax USB charger pack ~ 27 euros http://www4.fnac.com/Shelf/Article.aspx?PRID=1917203 Very nice set: USB Car charger + USB Charger (very small) + USB A male with zip cable + 7 different plugs adapters. I tested N770/N800 plug, Sony-Ericsson K300i plug, mini USB plug for charging bluetooth GPS globalsat BT-359. Note: I could not find a brick and mortar store selling the Nokia CA-100 USB to N800 plug adapter - I tried 5 stores in Paris (and it seems more expensive than the Mayama pack anyway...). ___ maemo-users mailing list maemo-users@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-users
Re: Experience with N800 portable autonomous battery charger
Laurent GUERBY wrote: So I went another route and bought: - 4x AA NIMH batteries with charger (1), - a USB battery extender with room for 4xAA (2) - a USB to N800 power plug adapter, part of a quite complete charger and adapter pack (3) Where'd you find the USB - N800 adapter? Even that much would be useful, as the N800 could then be charged by any computer or cigarette lighter adapter. -- Use OpenOffice.org http://www.openoffice.org ___ maemo-users mailing list maemo-users@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-users
Re: Experience with N800 portable autonomous battery charger
This works fine with my N770: http://www.recharge4.com/ 2007/7/22, Brad Midgley [EMAIL PROTECTED]: Laurent Did someone else tried something along these lines? I was looking at something similar with the microsolar AAA to usb (with small solar panel). In theory if you leave it in the sun where it won't get too hot it will charge back up over a day or two. It is only AAA so it might not be able to do an empty-to-full charge on the n800. http://www.21st-century-goods.com/page/21st/PROD/SM400 I have a usb/power adapter but not the microsolar yet. I noticed if you run the n800 down until it turns itself off, then it will get into a sort of reboot cycle when trying to charge it from usb. It doesn't seem to be taking a charge while it does that. Maybe it's trying to pull more than 500mA. Brad ___ maemo-users mailing list maemo-users@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-users
Re: Experience with N800 portable autonomous battery charger
James Knott wrote: Laurent GUERBY wrote: So I went another route and bought: - 4x AA NIMH batteries with charger (1), - a USB battery extender with room for 4xAA (2) - a USB to N800 power plug adapter, part of a quite complete charger and adapter pack (3) Where'd you find the USB - N800 adapter? Even that much would be useful, as the N800 could then be charged by any computer or cigarette lighter adapter. I ordered this from boxwave and it works well. http://www.boxwave.com/products/minisync/minisync-retractable-cable-nokia-e62_2097.htm My Dodge Magnum has 3 cigarette lighters...which somes in handy. One at front dash is for powering my ST5111 tablet on RamMount. Another is in console...I put cigarette 2 usb hub in there and since console has routing holes the cables can squirt outside where you connect device and place inverted in cupholder or something. Another DC socket at tailgate...for blender/parties. If you have 2+ devices any of the mini/micro usb hubs work excellent as recharging stations. See Targus...and get one that's powered. I'm glad us consumers finally have a standard charging solution. It's liberating to bring single usb cable for recharging your stuff. ___ maemo-users mailing list maemo-users@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-users
Re: Experience with N800 portable autonomous battery charger
On Sun, 2007-07-22 at 10:12 -0400, James Knott wrote: Laurent GUERBY wrote: So I went another route and bought: - 4x AA NIMH batteries with charger (1), - a USB battery extender with room for 4xAA (2) - a USB to N800 power plug adapter, part of a quite complete charger and adapter pack (3) Where'd you find the USB - N800 adapter? Even that much would be useful, as the N800 could then be charged by any computer or cigarette lighter adapter. I purchased (in Paris - FNAC Forum des Halles) a Mayamax USB charger pack for 27 euros: http://www4.fnac.com/Shelf/Article.aspx?PRID=1917203 It's in french but there's a picture so you can see what the pack looks like. Very nice set: USB Car charger + USB Charger (very small) + USB A male with zip cable + 7 different plugs adapters. I tested N770/N800 plug, Sony-Ericsson K300i plug, mini USB plug for charging a bluetooth GPS globalsat BT-359. Note: I could not find a brick and mortar store selling the Nokia CA-100 USB to N800 plug adapter - I tried 5 stores in Paris (and it seems more expensive than the Mayamax pack anyway...) Laurent ___ maemo-users mailing list maemo-users@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-users
