Gregg,
I also bought one of the cheapie replacememt batteries for a Dell 610, and had to exchange it twice in the last 6 months.  Add return shipping plus exchange fee, time lost,  I'm getting closer to the cost of a Dell.  The battery came with instructions - charge it fully, disconnect power supply, run it dead and repeat.  The third battery seems to be ok after 2 months, the first two didn't hold a charge after 2-4 weeks.   I'll know more in a few more months.  Runs my old Dell D610 around 1.5 hours, I only plug in the charger when the battery is low or dead now.  I'm thinking of removing the battery at home when I'm plugged into AC and it's fully charged.  However, some laptops won't run without a good (or bad) battery installed.
 I've read of zapping the old batteries with a large power jolt such as an electric arc welder can supply, but it sounds too risky to me.  The replacement battery is supposed to be lithium-ion, but the power cycling is more akin to what you should do with the old nickel-cadmiums (Ni-Cds) to avoid the memory affect.  I haven't cracked the case open on the replacements yet to see what's in them, but they feel similar in weight to the original Dell battery.  
Paul Hachmeyer

-----Original Message-----
From: Personal Computer Hardware discussion List [mailto:[log in to unmask]] On Behalf Of Gregg Pfaff
Sent: Monday, March 21, 2011 11:58 AM
To: [log in to unmask]
Subject: [PCBUILD] Dell Latitude D620 Laptop battery

Hi group,
_*Is there a better battery out there that will last more than 6-12 months*_. I bought a cheapy from a store on Amazon because I'd heard the Dell batteries are expensive and won't last much longer but, I think it was going bad by 5-6 months old.

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