40-70 A/H prismatic cells for Vectrix

NISSAN LEAF. SET IT AND FORGET IT.

If you have the leaf cell you can keep the cooling fan installed and that would most likely solve the extra hot climate problems. leaf did have heat problems on some cars that were in (airazona and nevada and new mexico-USA) but they fixed the problem and the leaf does not have cooling fans. I bumped up a couple of threads for you to look at. hope it helps.

The early Leaf cells (up to 2012, I think) had more issues with heat. The later models (2013+, I think) are supposed to have a change in the chemistry. Any battery will have an issue with heat though, just to a lesser extend on some vs. others. I don't know if the later/latest Leaf chemistry is "good enough" for the ambient temperatures that you guys are looking for.

If you have fans for the battery, all you are doing is cooling it or heating it up to ambient temperature faster. And in hot climates, I think if you charge in the sun but store the bike in shade most of the rest of the day, having fans may help or make things worse - depending on the time of day you use the fans (for charge or ride).

Unlike the NiMh batteries that do heat-up during equalization phase normally, the Li should not heat-up during a charge. Nor should they heat-up during discharge on the Vectrix, unless driven at 100% most of the time. Therefore, charging or riding your battery temperature should stay pretty constant without air intake to the battery. Say the day temperature of the air is 40C and night is 20C - the average might come to something between 20-30C and that would be your battery temperature if your bike spends about the same time at 40C as it does at 20C. If you, however, have fans that blow 40C air during charge/ride, your battery will heat-up faster and be above average temperature vs. if you don't have these fans. Conversely, if you have fans that blow 20C air during a charge (or ride) - your battery will cool-off below the average temperature without fans.

Also, the battery is very well insulated from the outside (and can be even better insulated). The battery temperature will change very little during a couple of hours in the sun vs. where it was before that. The inside under my rear seat does not heat-up much after an hour in the sun where the seat itself is burning hot. The same would apply to the battery. Now, if you keep the bike in the sun all day, it will begin to warm-up, but at night, it will cool-off, so the average would probably be still a pretty reasonable temperature for the battery.

Hi,

Unless you can find prismatic very cheaply, you are far better off using Nissan LEAF cells. A/ they are half the cost and b/ they are ~30%+ more energy dense than any prismatic. They fit like they were made for the V (or like the V was made for them) and make for a very straight forward instal. The only issue may be getting hold of them. If you are in the US the the hybridautocentre should be able to sort you out. If elsewhere...? I am in the UK so your costs may be different.

Lots of info about using them on this site and others.

About 2012 Leaf Cells, What is the max ºC ambient temperature for riding bike and charging avoid damege leaf modules?
Allpeople who do a leaf conversion put off fan..
Leaf modules really not need BMS?

Thanks

Pd: very interesting http://www.electricvehiclewiki.com/?title=Battery_Capacity_Loss

My summary:

At 60% SOC, lithium-manganese batteries have a little over 8 year life at 21C (70F) but only a 5 year life at 32C (90F).

In order to prolong battery life, GM uses just 65% of the Volts battery capacity, setting the limits at about 22% SOC on the low end and 87% SOC on the high end.

Batteries should be stored at the optimum storage state of charge which is between 30% and 40%

SAFT LiNiO2 cells: The cells were tested in 30% DOD regime (5000 cycles) with average energy fade rate at 4.0V at 0.000704% per cycle and 60% DOD regime (500 cycles) with average energy fade rate at 4.0V at 0.00430% per cycle.

Another report, which does not specify the specific battery chemistry, shows a graph of remaining battery capacity vs number of cycles. The results (with cycles normalized to full cycle in parentheses):
• 100% to 0% - 1200 cycles (1200 cycles)
• 100% to 80% - 12000 cycles (2400 cycles)
• 80% to 0% - 5000 cycles (4000 cycles)

For those that already own a Leaf, there are a few things you can do to minimize battery capacity loss:
• Keep the state of charge in the 30-40% range (on the Gid meter) as much of the time as reasonably possible. This roughly corresponds to 3-4 fuel bars for a new Leaf. Charge to 80% or 100% right before you need to make a longer drive.
• Shallower cycling (DOD) of the battery pack when possible. For example, two cycles of 60% to 30% SOC rather than one cycle of 90% to 30% should be better for the battery pack.
• Avoid parking in the sun when possible. Solar loading may increase the yearly average battery temperature by 1.3-3.1 degrees Celsius for a vehicle always parked in the sun (based on studies of the Prius, Media:HEV_Battery_Life.pdf)
• Drive and accelerate more slowly and more efficiently. This will have two effects:
o Minimizing waste heat (estimated to be 1% at 10 KW power draw, 3% at 30 KW power draw)
o Reduced cycling of the battery for the same number of miles driven, which will reduce cycling losses

So, maybe vectrix conversion must preserver fun in hot weather and if don´t need extra range maybe best charge at 80 % (around 3.95 volt each cell I think) istead of 96,7 % (4.15 v) and discharge to 30-40 % (3,75-3,85 volt each cell).

actually，they are nearly same, i didnt find much different between them after i test

Leaf cells, even 2017 Leaf cells, degrade in anything above moderate (<85F or so) heat. I'm talking about actual cell temp, not air temp. Actually, the 2016/2017 30kwh cells don't seem as robust, so far, as the 2015 24kwh "Lizard" cells. They may even be worse than the 4/2013-2015 cells. What I've been doing with my (formerly Kocho's) Leaf-powered VX-1 is keeping the bike in a cool garage, and only charging it when my primitive top-of-pack thermometer reads below 76F. I'm even planning on reinstalling an old window A/C unit in a garage window, for nighttime cooling during heatwaves. I also don't fully charge the bike until I'm about to use it, storing it at 8-14 charge bars.