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A few things to consider:
1. Although they are cheap, I don't think you will be able to get satisfactory performance from any salvage packs. They do not use power optimized cells, and are designed to be discharged in an hour or more, not a minute and a half. Tesla packs can output a ton of current, but they do that by having a massive pack that would blow your weight budget.
2. You have to consider both power and energy, especially when looking at ultra high C rate cells. John Metric's cells are unsurpassed for ten second drag races; his best ones can do peaks of 200C. But for a ninty second race, you are only discharging at a rate of no more than 40C or you run out of energy.
To be more explicit, you need 20Ah to sustain 800A for a minute and a half. John's cells are only five Ah, and you wouldn't be able to get quite that much out of them in race conditions, so you would need five in parallel.
That isn't to say they wouldn't work; they would work great, and voltage sag would be limited since you wouldn't be running them anywhere near their power limit. But you are paying for a feature you aren't using (ability to drain in twenty seconds) so it's not super cheap. If you went with with a 96S5P pack, at 25 cents a pop you are looking at $12,000 in cell cost alone.
1. Although they are cheap, I don't think you will be able to get satisfactory performance from any salvage packs. They do not use power optimized cells, and are designed to be discharged in an hour or more, not a minute and a half. Tesla packs can output a ton of current, but they do that by having a massive pack that would blow your weight budget.
2. You have to consider both power and energy, especially when looking at ultra high C rate cells. John Metric's cells are unsurpassed for ten second drag races; his best ones can do peaks of 200C. But for a ninty second race, you are only discharging at a rate of no more than 40C or you run out of energy.
To be more explicit, you need 20Ah to sustain 800A for a minute and a half. John's cells are only five Ah, and you wouldn't be able to get quite that much out of them in race conditions, so you would need five in parallel.
That isn't to say they wouldn't work; they would work great, and voltage sag would be limited since you wouldn't be running them anywhere near their power limit. But you are paying for a feature you aren't using (ability to drain in twenty seconds) so it's not super cheap. If you went with with a 96S5P pack, at 25 cents a pop you are looking at $12,000 in cell cost alone.
