Problem with New Battery?

I searched this forum for an answer, but didn't find anything related to my problem. The hard drive on my 6g iPod Classic 160GB recently failed, so I ordered a replacement drive. Since I was going to have the case open, I decided to replace the battery at the same time.

I installed the new drive, but when I connected the battery to the main board, the hard drive began cycling on and off every couple of seconds. The display would show a grey background with the Apple logo for a few seconds before going blank. This repeated without end for several minutes before I unplugged the replacement battery. I thought this might be due to the battery being discharged, so I connected the original battery to the main board. The hard drive spun up and eventually I saw the Welcome screen where I can select a language. This confirmed the original hard drive was bad, but has me concerned about the new battery.

I removed the old battery, removed the new hard drive, and reconnected the new battery. I then connected the iPod to a wall charger and let it charge overnight. I didn't want the hard drive cycling during this process.

Before I connected the wall charger, the display showed an image of a battery with a yellow warning triangle. As soon as I connected the wall charger, the screen changed to the Apple logo, then a large red "X" with Apple's website address below it. This is likely because there was no hard drive.

The next morning, I installed the new hard drive and reconnected the new battery that I thought had been charging all night. The iPod did the same cycling on and off that it did the first day. I removed the new battery and reconnected the old battery, and the iPod came to life with the Welcome screen. I put the new battery back in and connected the now cycling iPod to the wall charger for several hours, thinking it would eventually charge the battery to the point where the drive would stop cycling and all would be right with the world. Sadly, this was not the case, as the cycling never stopped. In frustration, I put the old battery back in and the iPod functioned properly.

I connected the iPod to my Mac and restored it through iTunes. I also transferred the songs and podcasts and it appears to work great with the old battery and new drive. I have not snapped the case halves together just in case there are more experiments to perform.

Question 1: Is the hard drive and display cycling indicative of a low battery?

Question 2: Can the battery charge while the hard drive is removed?

Question 3: If I leave the hard drive installed and connect the iPod to a wall charger, will it ever stop cycling?

Question 4: Is is possible that I have a defective new battery?

Without replacing that new battery with another, you're not going to know if it's defective or not. It does sound like the battery is either defective or of the wrong type.

Thanks! The iPod works great with the old battery, but not with the new battery, so I think it's the battery. I didn't know if there was a secret process I was supposed to initiate when replacing the battery.

I purchased this battery from a UK distributor and it fits perfectly in the iPod. I asked the distributor the same questions, since it also services iPods, but I'm still waiting to hear back from it.