Scott, If there are 18 strings at 80 cells in series each (if that's what you meant), the voltages add for 120V, but it's still 3 Ah. Then putting 18 of these strings in parallel, the total Ah is 18 times 3 Ah = 54 Ah. The cell watt-hours = 1.5V times 3 Ah = 4.5 Wh each, and it's limited by the weakest cell in the string. If you can stand diode drop, put a diode in series with each string to a summing junction (the output). The voltage is then 120V - 0.7V = 119.3V for silicon diodes or 119.6 for Schottky diodes. Whichever string has the highest voltage will discharge first, dropping to where the next string adds more current, and very shortly, all strings contribute equally. Frank
_____ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Scott Kuzma Sent: Monday, January 14, 2008 3:38 PM To: [email protected] Subject: [FLEAA] Battery information... Greetings everyone, This is Scott from the meeting that we had this past weekend. I came up with an interesting idea, but have no idea if it's possible. Basically, what is there to stop the use of a Lithium AA battery from being used to power the vehicle? I have found a AA with a 3ah rating at 1.5 volts. If you bundled at least 80 packs together, you would get the needed 120 volts. If each pack had 18 units within it, totaling 1440 cells. 1440 x's 3ah = 4320ah. I'm not familiar with how many ah would be needed. Can anyone provide an estimate for a 2500 pound car. The other concern is that Lithium powered EV's seem to always have a heavily detailed diagnostic system for the battery packs. How ultra-critical is this? If I had a highly efficient cooling system to maintain the battery temps in a safe range, would I also need to monitor the voltage of each battery pack? I'm trying to figure a budget-minded way of doing this without an exotic charger/controller. Pie in the sky? Throw me a bone. ~Best, Scott Kuzma
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