Battery Charging Problem?

[ptoki]

I had netwalker unused for a while. After plugging it to charger and booting it started to behave oddly.

Netwalker works fine but charging led (the one on netwalker) blinks and unit will not charge more than 70%.

When booted from halt witch charger unplugged it shows 10-12%. After just plugging charger and unplugging charge jumps to 70%.

I had left it charging (with blinking) for over 24h but it behaves the same.

Can any one suggest what happened?

I wanted to use it as small home media center for music and internet radio and for email but now I dont know how it will behave.

[ArchiMark]

Perhaps something about battery calibration went wrong due to not using netwalker for some time, battery level discharge too much?

Not sure how to recalibrate battery or reset system on this...as I don't have netwalker anymore....

[deluxe]

Perhaps something about battery calibration went wrong due to not using netwalker for some time, battery level discharge too much?

Not sure how to recalibrate battery or reset system on this...as I don't have netwalker anymore....

A fairly standard way to recalibrate batteries is to discharge them fully, then charge all the way up to 100% (or as far as it'll go). This recalibrates the charging circuitry essentially, makes no change to the actual battery.
It may need repeating to achieve accuracy.

If the Netwalker won't actually turn on, making discharging the battery fully difficult, I'd remove the battery, then hardwire a small bulb of appropriate voltage in to the terminals to drain it. Then put the battery back into the Netwalker and leave it overnight to charge.

[ptoki]

Deluxe, thanks for hint. I will try to fully discharge netwalker. It is alive so it should not to be a problem.

ArchiMark, this unit was yours some time ago

[deluxe]

Often I have had a seemingly dead battery in a laptop or similar. Leaving
it on charge for an extended time, and discharging it a couple of times has often helped that
battery to recover.
Don't despair ;-)

[ArchiMark]

Deluxe, thanks for hint. I will try to fully discharge netwalker. It is alive so it should not to be a problem.

ArchiMark, this unit was yours some time ago

Oh yeah.....right.......

 

[ptoki]

Well, I have left walky plugged and couple days later charge led stopped blinking. After unplugging PSU walky switched off instantly.
I guess battery or charging circuit died.

 

I assume that even if I find suitable battery it will be too expensive in comparison to buy some other gadget.

Does any one know any source for information about putting some other type of battery to netwalker?

It would be acceptable to put there even smaller battery but be able to use netwalker without power from socket...

[deluxe]

If the charging circuit has fried, then complete battery replacement sounds like your only option. But if just the cells have expired, then it's usually fairly easy and cheap to replace them.
If it were my device, I would pull the battery carefully apart, replace the cells, and charge it up. For about $10 for two new cells it's an experiment that would be well worth it IMO. If it fails, you can then start sourcing a whole new battery.

[ArchiMark]

Your best bet is probably Brett at Conics.net....

If you haven't dealt with him before, he's Australian guy living in Tokyo, and exporting interesting Japanese devices. So, it's easy to communicate with him in English. In turn, he can communicate with Japanese companies like Sharp over there in Japan.

Don't know if he will help you, but I know he was selling Netwalkers before. So, worth a try....

Check out his website and you will see how to contact him.

Hope this helps....

[ptoki]

Deluxe, thanks for suggestion but i think that cells are fine.
Netwalker was running long on batteries till some time ago.
Then was unused and then it started behave oddly.
So I think that cells are fine. But thats just my unprofessional opinion.

The way I thinked out is that I will buy external battery for 12V with charger.
I will plug it other way around so netwalker will be without battery and this new battery will be plugged as main power.
I think thats most safe and unproblematical way.

But first I will try to ask for advice guy which pointed by ArchiMark.
Just to ensure what might failed and how much would it cost to repair it.

Thank You both for constructive suggestions.

[ArchiMark]

Let us know how it goes, ptoki.....

Bit off-topic, but have you or anyone else ever got OS updated?

Just curious.....

[ptoki]

No, I stick to initial ubuntu. It works fine and I dont need to fiddle with it.

There is only one problem with netwalkers OS: video acceleration problems. But mplayer is usable...

[ArchiMark]

Thanks for your thoughts, ptoki.....

Sounds good then, overall....

[ptoki]

Thanks for your thoughts, ptoki.....

Sounds good then, overall....

A positive update:
My netwalker went sober after some charge-discharge cycles. Now it has about 30-40% of initial battery capacity but does not switch off when unplugged from charger.

I tried to open it and to fiddle a bit with battery but ended up with just looking at it and realizing its too complicated and too expensive to but replacement battery.

Now my netwalker acts as quick look into internet machine and mpd server.