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Below is a list of questions to be addressed as a result of this requirements document:
| Question | Outcome |
|---|---|
| Do we need a microcontroller? | Ideally, no. We don't need to broadcast any CAN messages. |
| What kind of protection do NiMH battery packs need? | Under voltage over the entire pack only. We will charge the NiMH cells at a constant C/20 rate such that they will self-balance over a slow charge cycle. Ideally the auxiliary battery will not be run for a long time so discharge balancing is not a concern. Overvoltage in NiMH at C/20 is not a concern. Temperature protection is not a concern. |
| How do we charge the auxiliary battery pack? | The auxiliary pack will be charged from the LV (12V) DC power rail in the car. A charge controller IC will be needed that will provide a NiMH charge profile. |