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Stamen
05 November 2014, 1219
I am looking at a Sevcon size 6 for my conversion. The specs sheet says.
nominal batt. voltae 72-80 VDC
max operating voltage 116 VDC

I am trying to understand if I can have a batt. pack voltage of 106 VDC nominal.

Thanks

Nuts & Volts
05 November 2014, 1248
Max charge voltage can be 116.4V fully charged. So 28s would allow you to charge to 4.157V per cell. So you lose about 2-3% of the battery but gain a lot of cycles doing that. So 27s is what you can do if you want 4.2V/cell fully charged.

28s puts you at about 102-104V nominally as the max nominal voltage you can have

podolefsky
05 November 2014, 2059
Depends on the cell chemistry. If it's LiFePO4, then 106V nominal is probably 32S (at 3.3V/cell nominal). If you charge to 3.6V/cell, that's 115.2V and you're OK.

If you're using most other chemistries that charger to 4.1-4.2V max, then what N&V said ^^^. Go with 28S.