Re: n810 extended battery
 

How quick is pretty quick? I am hemming and hawing on buying one of the 3600mah battery, as I will need the extra power for my backpacking trip through Wales. I was about to buy one when I saw your post with the problem on the batteries, so I am hesitating again. Just need to know how long I can wait before I make a decision and still get them before I leave.

Thanks!

Scott

Re: n810 extended battery
 

Ordered 10pm on 16th

Email 5am on 18th to say shipped by ETEN

Postman delivered (recorded delivery) 22nd

Re: n810 extended battery
 

Thanks for the quick reply!

Re: n810 extended battery
 

Have returned both the extended and slim Mugen batteries to Eten.

The extended one I did get to charge, but in use it was unreliable. The slim battery I never managed to charge.

Pretty sure its just the battery contacts, the standard Nokia one, the gold contacts on the battery look like they come closer to the edge of the battery and look more substantial.

http://www.mardibloke.co.uk/pics/N810ETEN/dsc_2878.jpg

http://www.mardibloke.co.uk/pics/N810ETEN/dsc_2879.jpg

http://www.mardibloke.co.uk/pics/N810ETEN/dsc_2880.jpg

http://www.mardibloke.co.uk/pics/N810ETEN/dsc_2881.jpg

http://www.mardibloke.co.uk/pics/N810ETEN/dsc_2882.jpg

Re: n810 extended battery
 

This is very discouraging news... :(

But thanks!

Re: n810 extended battery
 

Hmmm... seems like you could fix that with a little solder. Then again, if you tried and it didn't work, you probably would have a hard time sending it back.

Re: n810 extended battery
 

Eten have been good about it in email contact, have emailed them the photos too in the hopes that they can get the product improved.

Will keep the thread updated once the batteries arrive back with Eten and see what they say.

Sure, wedging some paper against the battery got the extended one working, and you could modify the contacts, but I feared I could damage my N810. So better to give feedback to the supplier and hope the product gets improved.

FWIW I quite liked the extra "bump" with the extended battery cover, made it easier to hold and use the keyboard.

Re: n810 extended battery
 

I'm sure the bump will mess with my GPS mount though... when I wind up ordering one I guess that's the time to make something myself...

Re: n810 extended battery
 

I'd dearly love a battery with 20% more life than the standard battery, and this 1800mAh extended battery sounds like it would do just that. However, I've also seen several reports on this thread of it either not working or delivering no more power. Has anyone used it and managed to get more life out of it than from the standard battery?

Re: n810 extended battery
 

Yes, I've tried it and no, you don't get anymore battery outside of the standard 7 hours use / 10 days standby. While it doesn't provide any more juice, it doesn't perform any worse than the standard Nokia battery and for the price, it isn't bad. I've been using it now for a few months and I don't have any issues to speak of, so even though I've read some have been given a defective battery, mine is working as well as the day I got it.

Re: n810 extended battery
 

Has anyone tried the Energizer Energi To Go Instant Cell Phone Charger with the n810? Does it work? How many extra hours does it give the n810? I'm going to be on a 11 hour flight in a month or so and my n810 is both my music player and ebook reader, and I'm looking for an inexpensive external battery to give me some extra time. How well does this one do?

Re: n810 extended battery
 

The Energizer device uses 2, AA batteries and costs $20.
Do a search on this forum for the Tekkeon MP1550. It uses 4 batteries and it's $15 at Newegg and eCost.

Re: n810 extended battery
 

I can get the Energizer device for $8.00 on ebay (from a reliable seller), so I'm undecided. Has anyone used the Energizer device on the n810?

Re: n810 extended battery
 

Any battery extender will somehow helped when the tablet battery is NOT flat. But when the battery is flat, 2 AAs or 2 AAAs are too small to be useful, http://www.internettablettalk.com/fo...ad.php?t=20117. I am looking for something like 8 AAs battery extender, have not been able to find any. Currently I am using this thing, which I got it for $32, http://www.amazon.com/Black-Decker-C...440712&sr=8-14. I have NOT been able to run it flat with my tablet :-). Unfortunately, I just checked, amazon.com has now put the price at 95$.

bun

Re: n810 extended battery
 

I'm considering building one with 4 D-cells (4.5 Ah). It's really nothing more than a battery holder, a diode and a plug (charging is done with separate chargers), but I'm waiting for my Pandora to see what exactly it's charging specs are.

I have a 4 AA-cells extender (originally meant for the Archos PMA430) and it's capable to somewhat preserve the state of my 770's internal battery while it's running, but not to charge it fully, not even with regular alkalines. Still, it'll more than double the 770's battery life and on long flights, that's all one could ask for (danged crappy inflight movies -- grumble grumble).

Re: n810 extended battery
 

I am luckier than you, I already have the tablets :-)

I also have a battery holder that holds 8 AAs. I did surgery on an instrument and now it looks like this. see attached pics.

I want like to know how to make this into a 8 cells AA battery extender. I guess, because of 8 X 1.5 = 12 V, I may have to have a step down, and a diode and a plug........I wish I know a little bit more :(

bun

Re: n810 extended battery
 

If you're connecting them in series, 8 AAs do indeed provide 12 volts. But how about you wire them up in two parallel blocks of 4 AAs? You could try a regulator (the 7805 seems appropriate) but that would

a) limit your output power to 1A (unless you use two 7805s in parallel) and

b) I'm pretty sure the 7805(s) would waste more power (heat) than my suggested solution of paralleling two blocks.

Plugs are easy; I've cannibalized mine from el cheapo phone battery extenders. They usually come with all kinds of adapters but the main adapter is pretty much always an "old style" Nokia 3 mm plug. Some careful dislodging leaves me with 4 to 5 usable Nokia plugs with a bit of wire for soldering. If you "shop around" you may even find one that has all female Nokia sockets, great for adapting battery-powered gizmos to AC/DC power adapters (my house is filled to the brim with throw-away LED gadgets that now happily waste power from the grid). The rest is the dabbling of the solder and the crimping of the socks. ;)

Oh, you also need a 3mm to 2 mm Nokia adapter, of course.

Re: n810 extended battery
 

I am really sorry I wasted your time. I am no good in handy electronics unless with a step-to-step, buy parts here, put A into B etc diagram, I am going to take a pass. If you want my battery holder, the one show in the pic, you can have it free. I will mail it to you if you can make use of it. I have it sitting in the corner for the last 3 month.

bun

Re: n810 extended battery
 

I bought a battery pack from Proporta, it's Li-ion and has 3400mAH capacity. Unfortunately, it arrived a day to late for me to take on my last trip abroad but it's kept my N800 running for about 8hrs while streaming Internet radio over WiFi. That's abt 5 or 6 times what I get with the internal battery.

I'd thought of building my own using AA NiMH cells but the Proporta part was better value & more likely not to cause hassle at some airport security check.

Re: n810 extended battery
 

I'm sorry about the misunderstanding. It seems it would not be trivial to change the pack you have from a 12 volt to a 6 volt one -- not without some serious tinkering, that is.

As for schematics, I'm usually flying by the seat of my pants myself; my knowledge of electronics is seriously limited. This I know: the "7805" I mentioned is a popular voltage regulator that puts out 5 volts, regardless of the input voltage (within certain limits). It is however "limited" to outputting 1 ampere of power, which I believe is less than what the Nokia tablets need when running and charging. You can improve the power output by hooking up several regulators in parallel, which multiplies that power output. However, regulators like the 7805 are not terribly efficient: they achieve the voltage step-down by essentially dumping it as waste heat and to go from 12 to 5 volts, you will need a heatsink on the regulators.

What you (and I!) need is a so-called "switching regulator", a piece of smart kit that steps down the voltage by switching the current on and off really really fast. These guys sell them: http://www.dimensionengineering.com/DE-SW050.htm

They even sell "breakout boards", which let you connect things without even soldering; and you don't need a capacitor as they built one in for you. Make sure you read the fact sheet though, and the tidbit on the page about parallel mounting.

Re: n810 extended battery
 

No, it actually is trivial, if that's constructed like I think it is. Should have exposed wires you can solder to at every connection between two battery stacks. Actually, I think you can solder straight to the top of that battery contact visible there... What you need to do is find the connection in the center electrically (4 cells above, 4 cells below; should be the only internal connection on the same end as the outputs) and tap it. Now with the batteries all installed as indicated, the outputs will be +4 V and -4 V from there, but if you reverse the 4 cells on the - side, then they'll both be +4 V, and you can connect the "+" and "-" terminals together as +, and the center tap as -. Bingo! you've got a 4.8V/6V pack.

The only problem I can see is if the contacts don't contact right with the cells reversed -- if so, a dab of solder should build the contacts up enough to work.

Re: n810 extended battery
 

OK, I can take it from the middle to avoid a step down step, that sounds good. Now, is there any ready made USB circuit board to give me the output? Or, I would have to gut out some of the USB extender battery? Maybe this is something within reach :) .......... I will see whether I can gut out a USB circuit board from my collections. I think an 8 cell AAs will last longer than a 4 cell AAs, that is why I am interested. Of course, if I can buy one that would be better :-)

bun

Re: n810 extended battery
 

There are lots of DIY battery extenders at Instructables. I'm pretty sure several of them have handy diagrams. Basically, if you follow Benson's lead, all you need is a diode to prevent current flowing back from your tablet to the batteries. Or you could go to your local electronics store/Radio Shack and ask the friedly attendant what kind of diode you need (it depends on voltage and power throughput). and how you should solder it up (putting in a diode backwards kinda negates its purpose).

The 8 AA version will not only last longer, it might have actually enough oomph to fully charge a tablet's batteries: If you're using 2500 mAh rechargeables, you're providing a max of 5 amps to the charging plug, which it'll like.

Re: n810 extended battery
 

Actually 7805 can supply 1A (with proper heatsink) which should be enough, as the charger that I use for my N810 (not 100% sure it's the one it came with, just some Nokia charger I had laying around) supplies only 890mA.

I'm also going on two long flight next month (there and back again:) and pondering how to best handle this, my first thought was to hook up a step-down transformer (aka buck-regulator) to my RC helis battery (11.4V 2100mAh) which should provide plenty of juice, OTOH charging that battery on the other would mean taking the special balancing LiPo charger and a 12V power supply with me so maybe it's not such a great idea afterall... (unless I take two battery packs, in which case there is no need to recharge them). There is also what security thinks of the battery packs as to keep weight down they're not in metal casings, just shrink sleeve. They do look a bit suspicious...

Then a quick calculation about using simple AA batteries; rechargeable ones are typically 1.2V and 2100mAh, which means 4 is either not enough or just barely enough voltage when they're full to the brim; a boost-regulator (step-up transformer) would be needed. Alkalines are 1.5V and thus can provide enough voltage to charge for a while even without the booster.

Maybe I need to go and check out what the shops have to offer before starting to build some contraption that will get me "special treatment" at every security check along the way...

ps. LiPo is just as dangerous as Li-Ion when it gets damaged. In fact anything with similar energy density is inherently dangerous.

Re: n810 extended battery
 

The alkalines will only have higher voltage than the nimh for about 3 minutes or so...

There's a nice spec at forum.nokia on the different voltage and current windows the devices will accept. I don't remember exactly, but I think it had' 2mm charger plug' in the name. Was easy enough to find last time I needed it :)

Re: n810 extended battery
 

Ended up getting official Nokia "emergency charger" (1 AA battery, this definitely has booster), need to test it to see if it is sufficient for my needs (and if not I'll take it apart to check a few things [like what ICs it uses...])

Edit: Also found the spec (http://sw.nokia.com/id/3378ff2b-4016...on_v1_2_en.pdf) plenty of good info (though I wonder how much smarts does the power supply really need and how much of the actual charging logic is built-in to the devices)

Re: n810 extended battery
 

the 1aa emergency charger i bought from dealextreme (#3017295, aka "rainbamboo") did nothing for my n810. i'd be amazed if nokia makes one that works.

Re: n810 extended battery
 

True enough it worked for only few minutes, time to take it apart and see if any of the electronics can be salvaged for a frankencharger (cue lightning and mad genius -laughter)...

Re: n810 extended battery
 

I bought something similar from Dealextreme and get the same results. It's probably because of the lower tension (1.2v) of a rechargeable battery than the 1.5v of a regular AA battery.
I ended buying this and I'm now really happy.
Charge nicely my 770, even quicker than the original charger or than a regular USB port (claimed to deliver 1000mA, and the real figure must be close to this).
The included 18650 battery is rated as a 2200 mhA, but must be around 1800 mhA, and can nearly top up an empty tablet battery. As it's a 3.7v battery, it's like having a three AA pack.
And having a full size USB port is really handy to recharge all your gadgets. Can also be used with a Y cable to power your USB devices connected to your tablet.

Build quality is OK, and additional 18650s can be bought for a few $.

A must have for your tablet.

Re: n810 extended battery
 

Found two interesting ICs:

First is a freescale one where google search with the part number shows up with some pages in chinese and then pages on freescale forum with people complaining that they can't find info on the part (and other people hinting that it's some "secret" OEM chip which would explain why there is no public info).

TEC103 (charge logic), as this device could also charge the AA battery inside (if it was of supported chemistry), the "problem" is that it won't work even the other way with "wrong" voltages (so 4AA was no-go, had to try though). 2AA worked fine and the datasheet also says it's ok (I guess the device itself was made 1AA for size reasons)

With two AA alkalines it was drawing about 700-800mA from the batteries (the connection terminal is small and I didn't want to solder anything to it at that point so the connection was less than perfect thus not exactly accurate figures here, saw over 1.2A for a moment as well but that might have been a misplaced probe).

Now test charging N810 with two NiMH batteries, seems to work fine. Picture: http://www.qaiku.com/home/rambo/show...e6b542f9b2f9b/

Ordered the thing agent770 suggested (thanks for the suggestion). They claim 1A charge current then it's twice the USB spec, and the official Nokia charger I have around is 890mA so 10% increase there as well.

Re: n810 extended battery
 

What do you guys think of this: callpod fueltank?

http://www.callpod.com/products/fueltank
http://reviews.cnet.com/power-device...-33481171.html

Re: n810 extended battery
 

The idea looks solid though depending on how the adapters exactly work, they might be gouging you for money with them. Also on long trips there's the problem that you need AC to charge the battery pack in this one, standard batteries are easy to come by (just about) anywhere.

The specs say nothing of battery voltage, if it's single-cell LiPo (3.7V) then the 4300mAh is actually 35% less due to the need to boost the voltage to 5V for charging (minus any inefficiencies and the fact that you cannot deep-discharge LiPos and expect them to survive the experience)

Re: n810 extended battery
 

Did this refer to the battery voltage?
Output Charge Power 5.4V / 6.4V @ 500mA per port

Full list:
Electrical
Battery Capacity 4300 mA/hr
Battery Source Lithium Ion
Estimated Charging Time 2.5 Hours
Input AC Power 110-240V AC, 50-60 Hz
Output Charge Power 5.4V / 6.4V @ 500mA per port
Power Source Refuel via AC power

Environment
Humidity 5% to 90% Non-Condensing
Operating Temperature -10°C to 50°C
Storage Temperature -10°C to 50°C

Physical
Dimensions 3.4"W x 4.9"L x 0.722"H
Weight 7.3oz (207.0 g)

User Interface
LED Indicators Charge capacity indicators
Number of devices supported 2

Re: n810 extended battery
 

That's the ouput eg. charge voltage, but the question is whether the battery pack(s) have 1 or more cells in them, eg. what's the internal voltage. I would say it's likely 2 cells in series (which would conviniently give the 6.4V without boosting as long as the batteries are full, of course as they lose charge the voltage drops as well).

Current is not a problem for lithium batteries: my heli batteries are rated (as in can supply without damage to the battery) for 30 x capasity for burst and 25 x capasity for continous current, with 2.2Ah capasity this comes to 55A continuous current (at 11.1V nominal voltage thats 610W of power! [for about 2 minutes]) and 65A burst... If you short-circuit the battery expect very violent results...

Aside the main point: it just occured to me that the TEC103 can charge single cell lithium batteries too, so the frankencharger could be rigged to work with single 18650 as well (something I'll be sure to try once I get the torch agent770 suggested)

Re: n810 extended battery
 

Args, it took 6 days for DealExtreme to even get my order shipped, depending on luck it might or might not arrive before I leave...

Re: n810 extended battery
 

Anothar nice review from anythingbutipod.

I still prefer the external battery mentioned before. Just receive my new N810, and charge it without complaining (and the N810 is far more picky than the 770, for exemple, ny N810 refuse to charge with a genuine nokia phone charger, while the 770 did)
The callpod get double capacity, but is more than 2 times bigger, uses proprietary connector, and is nearlly 3 times more expensive.