Quote:
Originally Posted by Blue Bomber Man
I need to learn more about the life cycle of the batteries based on charge cycles. One battery was quoted at 300 cycles, which seems low if that means I could only charge it 300 times total before having significant losses (20%)
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Allow me to help you a little on that. Most of these life cycle numbers are based off of 80% or 100% DOD through ALL the cycles. Meaning if the cell is rated for 300 cycles at 100% DOD, it will endure many more cycles if those cycles never go below 80% DOD, and the gains in cycle life get disproportionate as you lower your average Depth Of Discharge.
Get a chart of the battery you're looking at, and see how it looks. If you over-capacity your pack, (say, to where a normal driving day with opportunity charging keeps you below 20% DOD), you divorce yourself from cycle life for practical purposes, and have to start factoring in chronological life. (Which is as yet very much a mystery with Lithium batteries.)
Personally, I'm researching the Zebra battery. Although it's horrendously expensive at the moment, there is very little in the way of information on life characteristics, and they have a high-self discharge due to the heaters, the energy density they promise leaves Lithium spitting out dust.
If enough solar can be added to my design to compensate for the heater requirements of the Zebra battery year-round, I'll be going with that over Lithium.
Also, while you've got access to that program, would you care to share your work output and/or do some designs for a small amount of compensation?
