Thanks you all for your help.
Just to update, we ran the batch jobs last night with lesser number of IDs (50 IDs instead of 100 we did earlier) in each jobs. We had 144 batch jobs for 7200 IDs. There were 18 jobs running at a time. And we had NO ERRORS.
But, this morning we executed another 55 jobs for 2750 IDs which ended with 50 errors.
Now, where do you all think the problem is? Is it something related to memory issue?
Regards,
Anupam