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View Full Version : I just destroyed a $30 battery!



arthurking83
19th March 2006, 06:52 PM
.......all in the name of science! :D

I've been looking at getting a CRV3-R rechargeable lithium battery for some time now, and I noticed Jaycar has them for sale! Naturally I got one!!

They been averaging about $20ish on ebay....but I'm really going 'off' ebay the more I hear about the scamming....(possibly 90% of all ebay activity :p )

So I get my $24.95 CRV3 and recharger pack and I get it home, only to find they are about 5mm longer than AA's :(

Won't fit in the Meridian (without hacking it up!)

I place it in the charger, and consign it to the scrapheap that is my sisters digital camera :rolleyes:

But it won't accept a charge! after 16hours, the charger refused to charge it!!

I took it back to Jaycar, to get my money back (stuff the sisters camera! ;) ), but we tested the battery etc..... AND that's when the penny dropped!

The battery supplied with the $24.95 charger is not a proper CRV3-R, but a CRV3 'use once'....the manufacturer claims is rechargeable 500 times!!
That's why the pack was so cheap, and a single CRV3-R from Jaycar(no charger) comes in at $29.95!! :eek:

So the salesman replaced my CRV3 with a proper CRV3-R, I'm laughing all the way home........ :)

So when I got it home I cut it into smaller pieces!!! .......$30 down the drain :confused:

BUT it works....and it works well.

I just finished the first testwith the Meridian on this battery, backlight on FULL, and she went about 5.5 hours, give or take 5 mins.
I had to go out this arvo and only after about 20 mins, I though to data log the NMEA output to see when the GPS turned off.

I only got about 7 hours, or so, from my 2400mAh NiMH's with very little(if any) backlight....so the CRV3-R's are looking good so far :)

I estimate about 20hours with backlight OFF, as the backlight on the Meridian uses about 3-4 times the power, of the GPS(with light OFF)

Oh yeah!....and that's with the Gilsson external antenna attached too...about 12mA power consumption there, roughly 5% of the GPS with backlight ON....


To fit the CRV3 into the Meridian(or any AA powered device) involved slicing the plastic sheath to reduce the battery lenght by 5mm.

I was worried there were delicate electronice lurking in here, and while there seemed to be some kind of solder holes on the battery cells, there was nothing on the plastic sheath to link the two cells.
That must be hidden at the other end where the batteries recieve charge.

Even with the sheath cut, the modded CRV3 woudl only fit into the Meridian, if 'forced' in.
But now the (battery connector) spring on either end was not helping.
Removing one end is not an option, as I wanted to be able to fit normal AA's, so forcing the CRV3 in and compressing the other spring with a jewellers screwdriver(or similar) was the only option.
It finally went in after 2 or 3 attempts, and then a small piece of foil had to wedged between the +ve battery terminal, and the GPS +ve contact pad.
The battery has flush battery ends (or recessed at the other end), but no +ve nipple to reach into the recessed GPS +ve contact pad.
The foil worked!!

Now to see if the 3.1 volts of the CRV3 is going to damage the Meridian???
(doubt it :D )


until next time.......

arthurking83
21st March 2006, 08:02 PM
:o

Ooops!

I nearly killed it proper!

I just finished doing some tests and compared to my 2400mAh NiMH Jaycar AA's

I get 14.5 hours with the MH(metal-hydrides) with the light OFF, and 8 hours with the light set to full ON..... :eek:
(I'm sure that's waaaayyy!! more than my last test, when the batteries were new :confused: )

With the 'new' LiIon CRV3-R battery I only got 5.5 hours Light ON, and 10.5 hours Light OFF!!!
(I don't know the mAh rating of these CRV3R...and Jaycar don't have them listed on the website catalogue)
They do have one battery listed, and it's rating is 1500mAh, but this is not th esame battery!
It's the one I got with the charger, that won't accept a charge!

The battery, that the Jaycar dude gave me as a replacement, was listed as $29.95, and is described as the CRV3R, second 'R' is for rechargeable.
The other type is some manganese compound that allows regarging for x cycles!

OK so I put the CRV3R back in the Meridian (easier said than done :( ) but I put it in the wrong way :eek:
Checked the GPSand battery and nothing seemed to work!!
I thought I killed it, and the end that I cut, has the vital electronic circuits, etc...

No volts, GPS was OK, but the battery lost a lot of charge in about 20 seconds of being placed the wrong way in the GPS (??) a quick charge has it working again ...*phew*

All-in-all....not worth the effort, and expense.....unless the CRV3R needs some charge cycles to get up to full cap!
(although I'm going to leave the CRV's in for now, get some charge cycles under it belt...and the Meridian now feels half as heavy!)

What amazed me was the way it held charge, then dropped like a lead balloon!

The NiMH had a gradual decline on the batt meter, but the LiIon held full charge for over 10 hours, then dropped in the last 10-15 mins.


Now... a couple of 2700mAh NiMH, would serve the GPSr well!!


:)

Les Addison
22nd March 2006, 12:44 PM
These things have me enthrauled , did some footwork on em ,supposedly 500 recharges.Seems to me would be a great thing if they only made them in single cell units ,the same size as AAs ,1.5 volts. They would sell millions of em..Les :confused:

arthurking83
22nd March 2006, 04:50 PM
....supposedly 500 recharges....

That's for the manganese dioxide version, I was playing with a proper Rechargeable version....

jindydiver
23rd March 2006, 04:17 AM
Thanks for the review

You just saved me (and maybe others too) a lot of hassle :)

arthurking83
23rd March 2006, 04:15 PM
I forgot to mention too...

The battery is 'salvagable' in terms of .....I can supaglue the end that I cut off and it will work as a normal CRV3 battery again.

I originally was looking of one of these for my sisters camera, and I was in two minds about ripping it apart....

curiosity prevailed! :D