Charging the battery
 

Hi everyone.

I noticed that the pdf manual for the N800 says that you should not leave the unit plugged into the charger with a fully charged battery. They also don't mention how long it takes to charge the battery.

So here I am ready to go to bed with my N800 not yet fully charged thinking that I either have to 1) unplug the unit and top it off tomorrow morning, or 2) wait up until this thing charges.

Is it unreasonable to charge the thing over night when perhaps the unit might be all charged up in 30 minutes?

Thanks for your help with this.

Re: Charging the battery
 

Is there not a self cut off switch like most devices have these dayz? I mean come on nokia. I usually just leave it charging. If i get up in the middle of the night, ill unplug it. but i usually forget. I'm sure it just decreases the over all life span of the battery. But you can always get a battery off ebay :)

Re: Charging the battery
 

"I noticed that the pdf manual for the N800 says that you should not leave the unit plugged into the charger with a fully charged battery."

I think they mean not to leave it for weeks on end; they are not referring to ten seconds after it is charged, or a few hours.

In any case, I have several batteries, and I have been charging them all night for the last six months with no noticeable problems.

Re: Charging the battery
 

OK kewl. That's what I thought.

Re: Charging the battery
 

BTW, does anyone know of a car charger? Nokia doesn't seem to have one listed for the N800's accessories. I was thinking about buying an inverter and using the wall charger, but a car charger would be smaller/more convenient.

Re: Charging the battery
 

Any recent Nokia phone-compatible car charger will work just fine. If you can get one with the small tip, you don't need an adapter.

Re: Charging the battery
 

The Nokia DC-4 is one that can be used with the N800/770. It is supplied with the Nokia Navicore GPS Navigation Kit for these units. Try the "Search" feature at the top of the page and you will find answers to any question you can imagine.

Re: Charging the battery
 

I realize this is an OLD thread, but I finally disciplined myself to time how long it takes to charge my N800's battery from fully dead to fully charged:

2.5 hours.

Your mileage may vary, of course, but in case anyone still wanted to know...

Re: Charging the battery
 

Its not a good idea to leave any l-ion battery plugged in after its fully charged, it shouldnt overcharge, but all l-ions have a finite number of charge/discharge cycles, when the battery is fully charged, while plugged in it will stop charging, it will slightly discharge, then recharge, rapidly consuming the limited number of cycles. Thats why laptop owners that spend 99% of their time with it anchored to a wall are often dismayed on that rare occasion they take it out unteathered and think they got screwed with a bad battery.

Re: Charging the battery
 

Only sorta, it really has more to do with the fact that laptops are damn hot, and even moreso on their mains charger. Hot + li-ion = bad news. We have no such heat issues with our NITs, so leaving them on the charger isn't nearly as much of an issue as for laptops (anecdotally speaking, I have 3 batteries in 3 devices, two of which are left on the charger—770s—almost all of the time and I haven't noticed any significant impact in battery life).

Re: Charging the battery
 

Actually, the number of recharge cycles (which is an educated guess, really) pertains to complete recharges, meaning that if you never let your battery drain beyond 50%, you should get roughly double the recharge number. "Roughly" implying here that there are so many other factors playing that you'd get laughed at if you complained about getting only 590 instead of 600 cycles. Also, tricle-charging is designed to have as little impact on the battery as possible.

LiIon's biggest enemy is the al-gorean climate of the car seat: Leaving your laptop in your car in the sun is enough to reduce its battery quality to an AA (provided the idjit who leaves a laptop on a car seat finds it even back upon returning, that is).

Re: Charging the battery
 

Li-ions are generally much more affected by time than by cycles; heat, as the General says, is a real killer, but it works by affecting the time rate of degradation. That's why they say to keep spare batteries in the fridge or freezer.

Also, charge state does affect the rate, so leaving it on the charger, hence always ~full, is slightly worse than cycling it down to near empty, and fully charging it; but not (substantially) because of the discharge/recharge cycles.

Re: Charging the battery
 

Actually... Regular deep discharges are just about the second worst thing you can do to a LiIon (second to leaving it in the blistering heat, that is. If you also count poking inside them with sharp metal objects, then it's the third worst thing). They stay much happier when topped off before reaching half discharge.

Remember: LiIons are a completely different beastie than NiCads; the latter really craves the deep discharges.

Re: Charging the battery
 

Hmm. I don't know what this did to the lifespan of my battery, but ...

It was starting to say Fully Charged rather quickly and then not showing that it had a lot of juice when I took it off the charger, and, indeed, it did seem to run out pretty quickly. So I did a total discharge, until it turned itself off, and subsequently it seems to take a much larger charge. Maybe that's theoretically true only for NiCads, but my experience seemed to show it worked for my N800's LiOn battery.

Re: Charging the battery
 

LiIons have a funky charge cycle. They go up from near empty to showing almost full capacity very quickly, but most of that is "ghost" capacity; if you don't let the charge cycle complete itself, you'll end up with what you might think is a defective battery. This is another reason why it's good to "top off" LiIons: You get less of the ghosting effect if you unplug them too soon.

So, if possible let the charge cycle complete itself (for the Itablets that means: Wait until the battery icon shows full capacity), especially in case of a deep discharge.

Re: Charging the battery
 

;)Well, depends what you mean by "deep"; I was thinking perhaps down to 30%; anything below that is just plain scary, as well as perhaps harmful... I thought that was okay, though obviously pointless.Yes, which is why a flashlight is a valuable accessory for NiCds; I will not run any battery very deep in devices when avoidable, so I periodically throw a random pair of (semi-used, waiting for recharge) batteries in a flashlight, turn it on, and put my solar-powered watch in front of it to recharge overnight. In the morning, batteries are cleansed, and watch is full. (And atomic synced, since I do it on a windowsill.)