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[Richard230]

Just as a comparison: my Power Tank 2014 S is rated at 14.2 kWh by Zero.  However when fully charged to 100%, the Zero app shows 13.34 kWh of (I assume) actual energy available. It is my understanding that the "nominal" battery capacity quoted by vehicle manufacturers is always less than the actual capacity, most likely due to an agreed-upon (wink, wink) convention by battery and vehicle manufacturers to inflate the numbers as much as possible for advertising reasons.   

[Doug S]

This may have been the case at one time, but I don't think it's how most panels are sold today. Most panels seem to be sold on a STC rating, which while completely unrealistic due to lack of solar heating taper, is at least physically possible to achieve. PTC is a more realistic rating and many panels do specify this rating as well.

I'm VERY glad to hear some standards have been created and sanity has been enforced in the solar industry...the last time I looked was years ago, when I was helping a friend solarize his house. There are other examples: EPA vehicle mileage estimates used to be wild "best case" numbers until the gas crisis hit in the early 70s and public sentiment forced them to review their testing technique, and to this day a computer's hard drive capacity is rated in powers of 10 rather than powers of 2 (the original usage, and more meaningful in a microprocessor context) because it looks better on paper.

You're spot on about how the maximum capacity works, but I can only think of Zero as a manufacturer that works this way. Zero didn't "have" to do it this way, they simply chose to.

Brammo Enertia Plus: 24s7p with 3.7V 10 Ah cells = 6.2 kWh nominal
Brammo Empulse: 28s9p with 3.7 10 Ah cells = 9.3 kWh nominal
Nissan LEAF: 96s2p with 3.75V 32.5 Ah cells = 23.4 kWh nominal; typically 22 kWh available.
BMW i3: 96s1p with 3.8V 60 Ah cells = 21.9 kWh nominal; typically 18 kWh available.

In 2010 Zero listed only the "maximum" capacity of their pack on their site. The current site still has an archive of their older bikes. The 2010 packs were 14s24p 2.9 Ah = 53.2V nominal, 57.4V maximum 69.6 Ah = 3.7 kWh nominal, 4.0 kWh maximum (if charged to 4.1 volts per cell).

In 2011 and later years Zero broke out their battery pack into nominal and maximum capacity. They continue to rate their battery packs like this today; in 2012 Brammo began rating the Empulse in a maximum rating fashion as well.

I didn't know other mfrs were better behaved; it sounds like BMW and Nissan are playing some specsmanship with their numbers but Brammo is just now getting on board. I'd have to imagine a standard will come along pretty soon so all mfrs will have to give more representative numbers...I certainly hope so!

[protomech]

BMW and Nissan both advertise the nominal capacity rating but preserve some capacity at the top and bottom, just like Zero does.

[Xenoilphobe]

It charged fully to 100% last night.   I love this bike  I just have a lot to learn about the battery management I guess. Thanks again for steering me to the bike. Overall it is a great machine.

[Kocho]

If the cells were somewhat non-equalized, which I expect is normal if the bike was not regularly charged for equalization, it could take more than one charge/equalization cycle to top-balance them.

Note that 100% charge does not mean you have 100% of the original capacity (whatever that may have been when new). Each cell will charge to the same state of charge level (voltage) as when it was new, but it will hold less capacity as it ages. Assume 100% charge gave you 40 miles when new. It might give you 35 miles a few years and thousands of miles later.

What I disagree with in guidance I've seen here, is whether to keep the bikes plugged in for extended periods of time when unused. While this does take care of potential cell disbalances and keeps the bike charged, I've seen research that is against topping-up just to keep the battery full. And that batteries should be stored at considerably less than fully charged, when not in use for long time. I guess, whether to keep it plugged in or to plug it in only once in a while, would depend on how bad the BMS and other components are in terms of unequally discharging individual cells. If there was no BMS and other components that are "on" when the bike is "off" that cause disbalances when the bike is not in use, then keeping it unplugged is better. If the BMS/other components are really draining lots and unevenly from each cell, then the bike should be periodically charged to avoid the battery going too low, and equalized every now and then when in storage, then drained half-way again for storage for the  rest of the off-season. Should be allowed to fully charge and equalize one last time before using it on a regular basis in the Spring - to maintain max capacity (otherwise, charge may not be able to achieve 100% due to disbalanced cells)...

Also, it is probably better not to charge to 100% every time and not to discharge to 0 every time. Research suggests that batteries lose less of their lifetime capacity if they are used in a narrower range of their SoC but charged more often.

[GBEV]

Uk nissan Leafs were slow to sell. Ours was built in 2011 but sold late in 2013!
I found out after a lot id digging they were stored at 40% charge for several years.
The best performng UK Leaf batteries are owned by a taxi company who buy their cars used and have 2 of their own rapid chargers. They are charged daily but rarely from empty to full!

To give an exaple they now have 2 Leafs over 2 years old with over 100.000 miles still with not only a full 12 battery capcity bars but better than nominal Ahrs!
I can't find any Zeros close to that mileage and most seem to fail motors or accesories long before that. Pity as I would love one
Hope that helps.

[Doug S]

I can't find any Zeros close to that mileage and most seem to fail motors or accesories long before that.

You need to talk to Terry Herschner. He's not there yet but he's not far off....60,000 last I heard, and that was a few months ago. He puts miles on VERY fast.

[GBEV]

Yeah I know of him from Transport evolved;
https://transportevolved.com/
Lots to entertain EV enthusiasts there.

I once went coast to coast in America on a 650 Honda 4 back in the '80s so well done that guy.

Taxis are commercial vehicles though and it is intersting to me, having had long discusions with the proprieters of the UK's Cornwall taxi company that something they are doing is better for Leaf Lithium Ion batteries than even Nissan ever thought was possible, they mainly rapid charge and do it most days owning 2 rapids. Even Nissan's Mr Andy Palmer popped in to say hello there!