V is for Voltage electric vehicle forum

MORE EMAX PROBS LOL

aidanworthington — Wed, 18 Nov 2009 23:01:36 +0000

Does any one know of a good london emax dealer or where i can get hold of a emax 110s motor wire. For some reason the insulation has become brittle and has split.
Or should i just make my own using armerd 415v cable and a seperate cable for the hall sensor.
Allso has anyone had the same problem as me and does anyone have any pic's on how to pull the motor apart and what conections are needed.
Or could i get away with joing the wires under the swing arm wire cover using my trusty gas soldering iron and some heat srink pipe. any help would be aprecated cheers

Sounds like a shopping list doesent it LOL

my vectrix

robwhite — Sat, 14 Nov 2009 23:47:42 +0000

Very Nice to ride and I get plenty of looks when out riding

Battery chargers for EV

Spaceangel — Fri, 13 Nov 2009 04:04:10 +0000

I found some switched mode chargers for EV use and listing them here. I already use Iota and Progressive Dynamics chargers for 48 volt and 12 volt use on my vehicles. They work so great on 144 volt vehicle use. The caps on input are 180 WVDC and are perfect for EV use.
http://www.cloudelectric.com/category_s/340.htm is for Cloud and http://www.evcomponents.com/ProductDetails.asp?ProductCode=CHWP-14408 is for EV Components. John Drake by the way has best prices for Iota and great support.

I have used Iota 48 volt chargers in three banks to charge my truck but using one charger is a lot better. Current is 8 amp now for water resistant charger vs 15 amp for each 48 volt pack of my 144 volt truck. The only drawback is charge times are doubled.

Fresch Electric Bikes

reikiman — Thu, 12 Nov 2009 16:26:01 +0000

An electric bicycle dealer in Huntington Beach, CA. Their line of bicycles appears to be from RMartinBikes.

Home Page:

Fresch Electric Bikes

Vectrix battery charged

DovG — Mon, 09 Nov 2009 03:32:46 +0000

Battery has been fully charged. It took 6 hours for the charging process to be completed for a fully depleted battery. I have since ridden and charged the battery 3 times, however, did not ride down to the battery's red light but to about 1/3 charge left. Range has improved since the first ride a week ago, from 50km actual to estimated 65km. Speeds range from 50km/h to 80km/h, mostly at 70km/h, (70%).

200 to 500 Watts Micro Power Grid Tie Inverter For Solar Panels

current-logic — Mon, 09 Nov 2009 03:10:51 +0000

Current-Logic.com has recently developed Micro Power Grid Tie Inverter @ 200, 300 and 500 Watts.

This is not a really new product. It was not because it is difficult to produce, but the market in China seems small. Because common citizen won't spend that price for 200 Watts solar inverter. And the smallest grid tie inverter in the domestic market is above 1KVA, and not worth the price for common citizens.

You can now sell the power generated by home-use solar panels to the power company. It is not a big money saver (or maker), but the device does help encourage people use green power.

Input 10V~28DC

Output 110/220 VAC, 45-65Hz

Peak Inverter Efficiency > 94%

Size 70*90*190mm

This device now has 3 types : 200W, 300W and 500W

At this stage we only sell in bulk and don't offer retail for the device. ODM/OEM available.
If you are interested, please contact us for more info. Price and quality are promising!

Upgrading from SLA to LiFePO4

moveon70 — Sat, 07 Nov 2009 20:59:51 +0000

Some of you have been following my project to upgrade my little 180W ebike.
I have all ready posted on upgrading the hub motor from the 180W 36V system to the 1000W 48V system.
I promised to post on the performance when I got my new battery, and it finally came in.

I ordered a 48V 15Ahr LiFePO4 battery pack with BMS and charger from China off ebay for ~$250 shipped.
I hooked it up to the charger after unwrapping. I found the charger shut off after only 10minutes, so that means it did not self discharge during the 6 week boat trip it took to get here. Thats good news.
Another note is how they made it. Its simply duct taped together, but over all looks fine. IF I want to change the shape, I should be able to remove the tape and change it how I like.

In just a few minutes, I had it in the scooter.

There is nothing under the seat. That silver cube is the whole battery.
OK, its not pretty, but I will clean it up as time allows.

I finally got to go on a real test ride.
Here are the results:
Top speed is ~20MPH using a GPS.
It goes about the same speed up or down hill, so the speed must be governed by the controller.
It has plenty of torque. If I put my feet on the ground and pull the throttle, the front wheel will come up (but no, it wont wheelie while moving).
I can go up pretty steep hills with out loosing speed.
So far, I have gone about 8miles on the battery, and there is no noticeable drop in performance.
I pulled over and checked, and nothing (motor, controller, BMS or battery) was hot.

The only downer is that some times when accelerating from a stop (and pointing up hill) the current shuts off and then back on and off making a jerking motion. Since it did not do the same with the SLA batteries, I am sure that this is the BMS which came with the LiFePO4 system. It is protecting the battery from over current, or under voltage.
This tells me that I should have bought the 20Ahr battery, not for the additional range, but for the increased supply current under heavy load. Still, this issue is not common, and over all the bike is very ride-able, and I do not feel the need to order a larger battery.

So, the verdict:
Fun little scooter. Since I started with such a small frame, it is really light and maneuverable. The small LiFePO4 battery in the floor does not weigh much. The whole scooter weighs 32kg. It seems like is has plenty of range, and is fast enough to be usable. Also it is an e-bike, not a scooter. Only need a bike helmet, not license or registration. I am happy enough with it to want to finish off all the details like new lights and key switch. Get the regenerative breaking working and so on.
-Mark

Laptop batteries for my scooter

moveon70 — Sat, 07 Nov 2009 20:30:49 +0000

At my work, we have a recycle tub for used batteries. I decided to try to make use of the used laptop batteries for a little stand up electric scooter by sorting through them and finding the cells that were still in good shape.

There are many types of Li-ion rechargeable cell chemistries. (scroll down this link)
http://en.wikipedia.org/wiki/Li-ion

Typically, laptops (and the tesla roadster) use Li-ion cells with the CoO2 cathode. LiMn2O4 cathodes are used in the "X-treme" Li-Ion bike. LiFePO4 batteries are quickly gaining momentum as the battery of choice for scooters because they are inherently safer. LiPo (lithium polymer) is some of the most powerful, but also the most dangerous.

OK, so, the most common size of the CoO2 cathode Li-Ion cells is called an 18650 which is simply the dimension of the cylindrical cell (18mm diameter x650mm in length). Here you can see how they are laid out in a laptop battery.

These cells do not last for ever. Their capacity diminishes over time even with out going through charge cycles.
That said, some cells will degrade faster than others, so in each laptop battery, there is likely some cells still in good shape. You can see that to make this work, you would need to start with a lot of cells.

These cells had to be taken apart one at a time and remove the BMS. If the voltage of the cell was below 2V, dont bother trying to salvage the cell. It has probably become defective. Any of the cells that have over 3V have a good chance of recovery.

A new 18650 cell has ~2Ahr capacity, and can discharge 4Amps.
http://www.alibaba.com/product-gs/235681810/Li_ion_Battery_Cell_for_SAMSUNG.html

I decided to put 6 in parallel so that I can discharge as much as 24A, and if the cells were new (which they are not) I would have a 12Ahr battery pack.

I did not have a spot welder, so I decided to solder the cells into a 6 cell parallel battery.

I then used 8 batteries to make a pack.

Now for the safety part.
I found a really cool BMS by ecity power to use for the pack.
You can order them off ebay for $40 shipped. (search for BMS li-ion)
Software and diagrams can be found here.
http://www.ecitypower.com/index.php?option=com_weblinks&view=category&id=59%3Abms&Itemid=93

It can handle 8-12 cells, up to 40A, and the voltages can be programmed by the computer for your specific battery chemistry. For the CoO2 Cathode, the cut off voltage should be 4.2V.

Unfortunately, I had trouble getting the BMS to recognize all 8 cells. While messing around with it, some wires touched and zap-pop, melted the wires. So now I am ordering another one.

Until then, I charged up each of the 8 batteries separately and hooked it up and rode it around.

None of the batteries got hot, nor did the voltage seem to drop on hills. When I get my new BMS in, I will be a little more brave on how hard I push it, and update the blog at that time.

Resources:

ecity power BMS

Desire Power E-bike LiFePO4 battery

joy.desirepower — Fri, 06 Nov 2009 06:21:18 +0000

The Outstanding Predominance of Desire Power LiFePO4 Battery
· Safe technology, will not catch fire or explode with overcharge
· Over 2000 deep discharge cycles life, 8times of lead acid battery, 3times of Ni-MH battery
· Can be safely rapidly recharged, fully charged 90% capacity within 30mins
· High discharge rate capability, 10C continuous, 20C pulse discharge
· Extremely low self discharge rate, at state of 100% SOC and normal temperature, less than 5% / 6months
· light weight: 1/3 of lead acid battery, 2/3 of Ni-MH battery
· Can be used safely in high ambient temperatures of up to 60 deg.C without any degradation in performance
· Does not contain any toxic heavy metals such as lead, cadmium, nor any corrosive acids or alkalis thus making LiFePO4 batteries the most environmentally friendly battery chemistry available

500W 48V electric kart conversion from salvaged electric scooter parts

aliekens — Wed, 04 Nov 2009 13:53:05 +0000

More information on this kart can be read at http://electrickart.blogspot.com