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Old 08-05-2012, 06:11 AM   #54 (permalink)
bwilson4web
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Location: Huntsville, AL
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Quote:
Originally Posted by redpoint5 View Post
. . . Would these cells be ideal for an alternator kill switch setup?

If I assume a 5% increase in FE using an alternator kill switch, . . .
Daox pretty well nailed it. In my case, I only have a very heavy, limited range, lead-acid battery for the eBike which has an effective radius of ~3-4 miles. I'm expecting the effective radius to increase to 15-18 miles and my work is 10 miles away. My dual-stack design means no 'range anxiety' and the modest charge rate, ~250-300W load, means any 110VAC outlet will work.

It is my expectation that the $800 of LiON cells and $200 BMS will give me a fair-weather, electric bicycle. It will also give light-duty, cardio-time during the commute (it still has pedals.) Yet I won't add much more time to the morning commute once I have the route worked out.

Right now, I'm buying ~10 gal every three weeks, call it $40/3 ~= $14/week commuting cost. Due to weather, I'm not expecting to go 'gas free' as much as cut that down saving about $4-5/week. So we're looking at $1000/5 ~= 200 weeks or nearly four years to achieve 'pay back.' But if I pull off another 30-40 lbs, it will be much cheaper than some exercise club bill. <grins>

Plus ... I get to sneak-up on pedestrians. <GRINS>

Actually the real advantage is getting some 'hands on' time with LiON batteries and a battery management system. The experience gained is the 'tuition in the school of hard knocks.' It will satisfy my curiosity.

Bob Wilson
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2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL
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