The warranty problem lies with the battery company, A123 Systems, and not with Hybrids Plus. A123 will not warranty the individual cells, so how can Hybrids Plus warranty a pack with 1000+ cells?

Hybrids Plus could, and actually might warranty their BMS, Battery Management System, the software, sensors, and controllers, but their hands are tied when it comes to the battery cells.

This is considered an "experimental venture".
The cells were not specifically designed for automotive use, but this area looks promising.