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Journal DaChesserCat's Journal: Gas going up, but still no EV

Well, gasoline has broken $2/gallon around here, and I'm still no closer to owning an EV.

I've almost given up on converting an existing vehicle to electric. Existing vehicles are heavy (typically upwards of 3,000 pounds), which will require a pretty powerful motor ($$$), more batteries ($$$), more supercaps ($$$), etc. What's needed is something smaller, lighter, which gets by on significantly less power.

I've been looking at stuff by R.Q. Riley, specifically the TriMuter. If they can do interstate speeds in this thing with a 16 hp Briggs and Stratton, it probably won't take much electrical power to get this thing up and moving. It's smaller, lighter, etc., which reduces the required power, required batteries, etc. It would cost about $3k to build one, which is the rough part. I mean, I can get a pretty decent used car for the 3 grand.

On the battery front, Lithium Ion prices continue to fall in price. I figure I can build a 20 kWh pack (good for a 100-mile range) for about $7K. That's down from $20K about a year ago, which is a big improvement. If I'm willing to go with lead-acid batteries, Exide has recently started building spiral-wound Valve-Regulated Lead-Acid (VRLA) Absorbed Glass Mat (AGM) batteries. One particular model, the 31XCD, has specs WAY above any other lead-acid battery I've ever seen. At 12 volts and 115 Ah, that's 1.38 kWh for one battery. At only 54 pounds, that's over 56 Wh/kg. Note: most of their batteries in this class are in the 30-35 Wh/kg range. 25-35 Wh/kg is normal for lead-acid batteries. If the specs on this thing are accurate, a 20 kWh battery pack would weight only 972 pounds (that's 18 batteries, which will give nearly 20 kWh at 80% Depth of Discharge). Most EV's have over 1,500 pounds of batteries (if they use lead-acid), so this is a major jump. I'm HOPING the specs are accurate, but they almost seem too good to believe. Since they're asking about $150 per battery, that would be <$3K for the battery pack.

That would put the whole idea a lot closer to "possible," even if it isn't too probable.

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Gas going up, but still no EV

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