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[flar]

Partial discharge is something Lithium batteries love as it extends overall life, nevertheless every time your plug the pack in is a charging cycle less on the battery life clock...which does not make a big difference in +2000 life cycles 

Either way, should be ok.

To be more specific...

Lithium batteries hate heat.  A full recharge usually heats up the pack quite a bit and so is less longevity-inspiring than quicker, cooler, charges.

Also, lithium ion batteries are rated in counts of "full charge cycles" which means 2 recharges from 50% equal one full recharge (more or less).  That's why they also quote a mileage approximation for the life of the battery, because the amounts of each of the charges don't have as much impact as the total amount of power put in over the life of it (every recharge being a full recharge will come up shorter in terms of overall mileage due to heat aging rather than shorter charges coming up short because you ran out of them in number).

[ColoPaul]

Also, lithium ion batteries are rated in counts of "full charge cycles" which means 2 recharges from 50% equal one full recharge (more or less).  That's why they also quote a mileage approximation for the life of the battery, because the amounts of each of the charges don't have as much impact as the total amount of power put in over the life of it (every recharge being a full recharge will come up shorter in terms of overall mileage due to heat aging rather than shorter charges coming up short because you ran out of them in number).

How far can you push that analogy?  Do 20 recharges form 95->100% equal one full charge?

[flar]

Also, lithium ion batteries are rated in counts of "full charge cycles" which means 2 recharges from 50% equal one full recharge (more or less).  That's why they also quote a mileage approximation for the life of the battery, because the amounts of each of the charges don't have as much impact as the total amount of power put in over the life of it (every recharge being a full recharge will come up shorter in terms of overall mileage due to heat aging rather than shorter charges coming up short because you ran out of them in number).

How far can you push that analogy?  Do 20 recharges form 95->100% equal one full charge?

The best information I've been able to find is all at the Battery University.  In particular, they have a chart of Depth of Discharge vs. number of cycles for Lithium Ion on this page.  It looks like 50% cycles can net you 50% more overall life compared to 100% cycles (multiplying the total cycle count by the %discharge == # of comparative "full" cycles), but 10% cycles actually provide slightly less life than 100% cycles (not enough to worry about, but still less).

(They reorganized their site and I can no longer find the paragraph that mentions that the problem with full discharges is the heat.  Still they have plenty of pages that go into depth about heat being bad for the batteries, and also that leaving a device constantly on a charger can induce heat as well - unplug those laptops from time to time even if you are next to a charger!

[oobflyer]

There's an outlet on the wall behind the bike 

[Lipo423]

Having a chat about lithium-batteries, is something quite interesting, and difficult at the same time...one of the main aspects to take into account is the chemistry, and the way it behaves (in our case is LiMnO2, or Lithium Manganese Dioxide), one of the safest chemistries in the Lithium-range.
The battery manufacturer is Molicel as far as I know. They range the discharge temperature from -20C to 60, and charge from OC to 45C. Quite frankly IMHO -20C is too low and lithium generally speaking do not like neither low temperatures, nor too hot...(this is quite confusing sometimes because anyone would say. What the h...is the right working temperature!!!)
I believe is in the 20-25C range...

I left this comments/suggestions about Lithium in an older thread

The battery life is a combination of time/charging cycles. Usually a high quality Lithium battery would last 5-6 years before loosing a reasonable capacity (they do not just die)...as soon as you respect a basic things:
- Never charge above 4.2V / cell
- Never discharge below 2.7V / cell, or storage a battery drained
- Avoid charging a heat pack whenever possible
- Charge at 1C max.
- When storaging for a long period of time keep the pack charged at 30-40% of total capacity, not at 100%...
- If you avoid deph discharge, you increase battery life/cycles
- Always check battery manufacturing year if possible.

[protomech]

lithium generally speaking do not like neither low temperatures, nor too hot...(this is quite confusing sometimes because anyone would say. What the h...is the right working temperature!!!)
I believe is in the 20-25C range...

Generally speaking that's true, but there are some cases where it's not.

Toshiba's SCiB lithium-titanate chemistry (used in Mitsubishi MiEV, Honda Fit EV, Honda Cub EV scooter) claims 95% original capacity at -10C and 85% original capacity at -30C.

[Lipo423]

That is true Protomech, it is a very good option for high rate capability, low temperatures and extremely long cycle life.  They are very safe, operate at a lower voltage, and can be charged faster (in theory they admit up to 10C charge).
The problem is their energy density, which is lower than other chemistries (for example the one in our bikes) - it is still reasonable as it goes above Nicd, but not as good for small vehicles.

At the moment a few manufacturers are looking at different cathode and anode materials with promising results
(Lithium-Air has a theoretical density of 10.000Wh/Kg...but laboratories only have obtained so far 700Wh/Kg) which is pretty good as today commercial products can only safely exceed 250Wh/Kg.

First prototypes should see the light in 2013, production in 2020 

[Richard230]

And speaking of Zeros and parking spots, today I went to see a movie at the local regional mall (Tanforan, located in San Bruno, CA). I was riding around their multistory elevated garage wondering where I should park my bike so that it would be in a safe location, when I noticed a couple of motorcycles parked on the sidewalk on the ground level next to a Sears side door. So I parked my bike there. When I came out from the show, there were a couple of the mall security staff checking out my bike. When I showed up they asked me about the Zero and seemed very interested in it. They told me that they saw it on their security cameras and the mall security supervisor said that one of the bikes that I parked next to was his. He said that I was welcome to park my Zero any time along the building wall and they would keep an eye on it with their camera.  Now that is what I call a nice welcome.  Maybe I should have if there was an electrical outlet near by?