HPLX.NET REVIEWS Times2 Tech NiMH Batteries

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Publisher/Manufacturer: Times2 Tech
Contact: http://www.times2tech.com; call 800 number
Price: $12 per pair  

About the Product

If you're having problems with power in your palmtop, and you frequently find yourself confronted by the "MAIN BATTERY LOW" warning, and you hate swapping out the batteries in the middle of a backup or while downloading a great file, then you're going to enjoy these batteries.

I have another review posted about Panasonic High-Capacity nicad batteries.  Suffice it to say that I am more than ready to swap out my Panasonic batteries for these new batteries from Times2Tech.

First, let's get a few things straight.  These batteries are rechargeable, but they're not the same as nicad rechargeables.  NiMH batteries generally have advantages over nicads: a higher capacity, and no memory effect.  However, they also have disadvantages.  They take longer to recharge, and they discharge rapidly even when you don't use them.  Whereas nicads might last four weeks in your desk drawer after a good charge, most NiMH batteries would be dead inside of a week.  These new batteries, however, are proving a new rule.

In these batteries, the chemicals inside are formulated differently than in most NiMH batteries.  The electrolytes are in a gel form, which eliminates the problem of the charge dissipating.  But come on.  These batteries are only 1350mAh.  How much better can they be than 1100mAh nicads?  The math is simple.  1350/1100=1.23.  So at most, you'd expect these batteries to last 23% longer than the high-capacity nicads.

Well, with this in mind, I decided to put these batteries to the test.  I ran three high-intensity tests: 1) continuous read from a high-power flash card, 2) continuous write to a high-power flash card, 3) connection with a PCMCIA modem.  All tests were conducted on a double-speed 200LX with a 6MB C: drive.  These tests were mostly the same as those performed on the Panasonic nicad batteries, with one exception: during the read test, the screen output was disabled on the Panasonic battery test.  On this test, it was not.  Thus, current draw may have been slightly higher during this test.

Test 1.  I set up a batch file to run CHKDSK continually on my flash card, and timed it with a stopwatch.  Not expecting the test to last too long, I started it around 6:00 in the evening.  Fortunately for palmtop users, I was wrong.  I was up until past midnight waiting for the batteries to die.  The result: the batteries lasted 6 hours and 9 minutes before the first "MAIN BATTERY LOW" warning was displayed.  6 minutes later, the palmtop powered down.  The total: a shocking 6 hours and 15 minutes.  This is more than double the time provided by the Panasonic nicads.

Test 2. Another batch file was set up, which continually wrote a string to a file.  This time, I could take advantage of the palmtop's built-in clock to help me out.  I recorded the time I started the batch file, and then just went to sleep.  When I woke up, the palmtop had powered itself off due to an extremely low battery.  I merely rebooted it and checked the time stamp on the file I'd been writing.  The result: the palmtop wrote for 5 hours and 12 minutes.  this is more than 10 times the amount of life provided by the Panasonic nicads.  23% is not an entirely accurate picture, eh?

Test 3.  I inserted my Simple Technologies Communicator 33.6 in the PCMCIA socket and connected to my ISP with WWW/LX.  I was expecting this test not to be so long, and I was right.  A PCMCIA modem uses more power than a flash card, especially during use.  I wandered around the web for a while, downloaded some utilities from SUPER, and checked out the news on Yahoo.  I checked my e-mail a few times, disconnected from WWW/LX, and dialed up a few local BBSes.  After a while, I got bored with that and dialed up my credit union's terminal and balanced my checkbook online.  Finally, I went back online with WWW/LX and checked the news again.  After two hours and 38 minutes, the palmtop finally powered down.  This was about 2.5 times longer than I got with the Panasonic nicad batteries, which previously held the record.

These batteries are also good because the voltage drop curve is similar to that of nicad batteries.  You can use high-current drain cards (or anything else that draws a lot of power from the batteries) without having the palmtop shut down on you.  That's hard to do with alkaline batteries.

Now, the only other question about these batteries was: are they truly free of the "NiMH curse," that is, the dissipation of the charge even without use?  Well, judge for yourself: the batteries have lasted for 35 days in a 200LX with nominal use.  For NiMH batteries, that's just fantastic.

There are only two downsides of these batteries that I can see.  One, they take about 16 hours to recharge.  However, with the length of time these babies last, you won't need to recharge them that often.  (Also, you don't have to worry about waiting until they're fully discharged to recharge them, or just doing a trickle charge daiy, since these batteries fit YOUR schedule.  You can charge them an hour here and an hour there, in high-current mode, without fear.)  A couple pairs should be plenty for most users to be able to have continuous battery power.  The other potentially troublesome part about these batteries is that they don't have a tip on the positive side.  The metal contact is just flush with the edge of the battery.  This means they may not fit in all devices that require a AA battery.  However, they work fine in the 200LX.  (And you thought HP was foolish for putting the spring on the positive side in the left half of the compartment. :)  

The Verdict

Buy these batteries.  Call up Times2Tech right now and order yourself a pair or two.  You'll be glad you did.   

Copyright 1999, David Sargeant.
Last Updated 1-2-1999

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