The mechanical structure of the battery is one thing, but we need to consider pack to system mechanics and the integration.
Battery to Vehicle Mechanical Integration
The total vehicle unladen weight can be around 2000kg and the battery pack can be 500 to 600kg and hence a significant portion of the overall weight. Hence a part of the crash system that cannot be ignored.
Maintaining mechanical integrity, but ensuring electrical and thermal isolation can be challenging.
The mechanical level of integration can also bring challenges when removing the pack for servicing as that then breaks the cabin waterproof seal.
Re-establishing that seal to its original IP rating on reassembly is where this gets tested in practice, and it is most acute on Cell to Body designs, where the pack’s upper closure doubles as the vehicle’s floor panel rather than sitting under a separate one – XPENG’s Sepa 2.0 is a named example of this. That raises the exact question our Cell to Body page flags but doesn’t yet answer: is the pack extracted for service leaving the top panel attached to the body, and if so, how is that boundary resealed and re-tested afterwards?
For a recent example of how pack-to-vehicle integration plays out in a production platform, see the Rivian R2 Pack – 2026 Update.
When looking at the mechanics of the pack it is important not to forget the busbars and control cables. These need to be secured and isolated.