I have a X-Treme XM-4000Li scooter. This scooter has 20 Thundersky 40Ah batteries. I have had the scooter about 1 year and have 6 bad batteries. I am wondering about converting to the GBS batteries. I hear they are safer and more reliably. Has anybody done this conversion? How hard is it? The GBS batteries must be the same thickness and height as the battery box is already too small.
Who's online
There are currently 0 users online.
Who's new
- eric01
- Norberto
- sarim
- Edd
- OlaOst
Support V is for Voltage
Look up their dimensions and compare. The dimensions on the Elite Power Solutions are for a 4-cell unit and include the end plates, but can be used for comparison. The GBS cells are not the same dimension - I think they are wider, thicker and shorter than Thunderskys.
But why get GBS cells? While my CuMoCo scooter came with them, they are still a bit of an unknown.
The quality and consistency of the newer Thundersky LiFeYPO4 cells is considerably improved and much of the well-taken criticism of 3 years ago is now out of date. Make sure you get "genuine" Thunderskys. The mfg. which is now called "Winston Battery Limited" (Winston Chung is the designer and founder - he poses in a Mao Suit with some nationalistic propaganda on his web site, but don't let that bother you).
I installed a new pack of Winston/Thunderskys on my old e-max. They balance easily and exhibit a voltage sag of only about 0.15 volts per cell at 2.5C in warm weather use, or about .2 volts in the cooler 52F mornings lately.
The service is slow, but the cheapest source for Thunderskys are here:
http://www.alliancerenewableenergy.com/
Your scooter does have a BMS, doesn't it?
OK, so why change. I read somewhere, it may have been on this forum that the TS style of battery is not allowed on vehicles in China. The TS style explodes and catches fire too easily. I have had 2 batteries explode in the past year. Also the connectors are very different. The style of connector on the GBS battery prevents accidentally touching across to another battery. The TS style battery connectors almost always touch and short while they are being removed. When I work on my TS batteries I stick pieces of cardboard in between the batteries and cover the adjacent terminals with electrical tape.
I am having trouble comparing the size of the GBS batteries. The sites I have looked at have the size of a 4 pack as 125X208X180 mm. So, which is the width and which is the length? I know that the 180 is the height.
My scooter did not come with a BMS. I am in the process of adding one.
You can contact Zehrbach at Zelectricvehicle.com. He has used both on scooters and can source what you need (currently using GBS cells and BMS, might be able to provide GBS BMS for thundersky cells). If you had a BMS, your cells would be holding up much better.
You can contact Elite Power Solutions and use their solution if looking for a full turn-key system.
Regarding dimensions, compare the GBS 40AH 4-pack and the 60AH 4-pack. It looks like the height and width remain the same but the length changes (cells thicker).
Good luck,
Motorcycles: 2011 ZEV Trail 7100, 84V, 60AH, 60+mph, Cycle Analyst, TNC throttle, modified charger. 2013 Kymco GT300i
Bicycles: 2017 Sondors Thin
Cars: 2016 Leaf SV, 30KWH pack. 2007 CR-V
Solar array: 5KW. Cost per lifetime KWH produced $0.073
Bi
I seriously doubt that there is any truth to the "explodes and catches fire' stuff. When testing, I accidentally discharged a cell completely to zero, then recharged it. The battery stayed completely cool - but lost a good bit of capacity, albeit much less than i expected. the only noticeable change was a bit of swelling when completely discharged. Shorting when making connections (a momentary short is no big deal even if it happens) is easy enough to prevent. Just hold the connection strap in place when turning the wrench - and don't drop straps or other metal objects on the pack. Wrap tape or slip rubber tubing on socket wrench extensions and screwdrivers. In other words, just use some care. GBS cells can shorted by dropped tools too.
I have been very happy with my latest Thundersky cell pack - 4 months of heavy daily use and no problems.
It is not surprising that you have some bad cells without a BMS. Have you ever checked cell voltages when charging? Without a bms, some cells can hit 5-6 volts instead of the maximum 3.7 - very bad.
To get the individual cell dimensions from the 4-pack dimensions, height is height, width is width and thickness = [pack length -(end plate thicknesses, about 1 cm)] divided by 4.
edit: Here are the dimensions:
TS: H=190 mm W=116 mm, T=46 mm
GBS: H=180 mm W=125 mm, T=49 to 50 mm (assuming end plates are 5 mm each)
An international standard for the dimension for these cells will be nice someday.
I converted 2 E-MAX 120S from Lead to 100Ah GBS Pack and I did more than 5000 Km on it using an Elitepower 30A custom charger ... so every day battery get charged at 30A (.3C) and
discharged in a few hours of running (about .4 .5 C)
So far (5000 km) both batteries and Bms works ok
Very impressive. How did you find the space for 100AH of these cells in a 48 volt scooter?
What range is being achieved from this conversion?
E-MAX start with 4 60Ah Lead Acid battery.
Each Lead is 260x210x170mm there are 3 Lead in the front compartment and one in the back , the front battery box measure 260mmx235mmx510mm , fitting 100Ah is easy and they fit
really nice beacuse a 48V 100Ah GBS pack is 260mmx232mmx500mm , there is just 10mm space left for closing the box and almost none space left on hight.
The range is a around 150-160km maybe more (I did 140 and there was some leftover , I still didn't push the battery all the way empty for a test)
On uphill the scooter is really much better ... GBS have a little higher nominal voltage (51 instead of 48) , the voltage sag is almost nothing ,1 or 1.5 volts ( GBS battery are rated 12C burst and 3C continuos , the motor can barely use 100 Ampere at full power, witch is just 1C from battery prospective ) and the scooter weight about 60kg less.
With lithium you can also be much "hard" on regen when going downhill.
So fitting the 100Ah GBS on E-max uses just 3/4 of available battery box , I thinked to put more batteries but thing was going to be too much expansive and used the money to get a faster (30A) charger
instead of standard (20A) charger that comes with the Elitepowersolution pack.
Zigalisr, how did you determine that 6 of the cells were bad? I have had my 4000li for about 7 months and recently took it apart to replace a faulty ignition switch. At full charge my pack measures 79.5V with the best cells at 4.07 and the weakest at 3.72. After a couple of hours it will equalize around 3.88 for the strongest and still 3.72 for the weakest. Still within spec I believe.
At low voltage, 65V, I found that all 20 packs measure exactly 3.28 V. Impressive balance without BMS after exaclty 4000 miles of use. What voltage are you measuring on the 6 bad cells?
2007 XM4000 came from the same GBS battery but in yellow shell when they got production license from TS,so that new blue GBS just change into another shell,but basic is the same.
Why don't use CHL battery ? it come with active BMS,which uses electromagnetism inductance principle for moving excessive charge of one cell to a not so full cell. This can work both during charging as well as discharging and even power off, but only limited to 1A or 2A small currents. The system is called active BMS or inductive BMS that uses cable to transfer higher currents between cells, in contrast to the usual passive balancers that "burn off" excessive charge of cells by heat resistance. Active BMS should yield higher efficiency than passive systems because the energy is mostly retained instead of dispated as heat, and could thus also allow slightly higher vehicle range.
So, why not use CHL batteries? Well because they are the same as ThunderSky and CALB. They has the same style connectors, the same chemistry, and the same problems with overheating. Do you work for the company that makes CHL batteries?
So, I say WOW. That voltage level is Wow 4 volts, the max I get is 3.3 - 3.4 volts. The cells most of the time are 3.3 volts, right when the charger is disconnected some can be 3.4 volts. The spec on these batteries is 2.5 to 3.6 volts.
Well 2 batteries exploded. While replacing the first one I took out all 5 packs. I have four, 3.6v chargers, like cell phone chargers. Charge each battery overnight to 3.6 volts. Then use a car battery load tester on each 4-pack. This loads the pack for 20 seconds. The load can be anything from 40 amps to 100 amps. Then if the voltage sag is more than 1.2 volts or so one of the batteries is bad. So I found 2 bad batteries that way. One battery sagged to 1.5 volts and the other to 1.2 volts after a 20 second load. Took the packs apart to ship the bad ones and found 2 were very swollen. These batteries will get very swollen before they explode. You really can't tell when they are strapped together into a pack.
Then got replacements, put them all back together and started riding again. After about 3 months of riding, another battery exploded.
These batteries are rated for 40AH. I use Cycle Analyst to show how many Amp hours I have used. If you don't have one, get one today, www.ebikes.ca/drainbrain.shtml. So, how far can I go on one charge? Well, the first battery exploded after 32 AH, and the second exploded after 18 AH. Now I can feel when the pack is having trouble and plan my rides for 20 AH or less.
swollen means overheat and big impedance inside cell
we are difference,see http://visforvoltage.org/forum/10381-cell-impedance-thundersky-and-chl-lithium-battery
We are not overheat because of low impedance,see attached temperature after 19 minutes 3C discharged,it is very cool.
ZigaLisr, how many miles on your 4000Li? I have 4330 on mine and have owned her for 8 months. Yes some of my packs measured over 4.0 at full charge. I had probably 6 out of the 20 that measured 4.05 to 4.09 right after charge, but that quickly subsided to around 3.88 after an hour or two. My Thundersky charger has to go into pulse mode to get them that high (both lights green, leave plugged in for an hour after they first go green). My very weakest cell was 3.52 after both lights went green, but that came up to 3.72 after some time on pulse charge.
Are you running in high temperatures that are making your batteries explode??? I live in Phoenix AZ, and I cannot imagine it being hotter than my rides have been the past 4 months. I have ridden 25 miles in 115 degrees, which I do not recommend. But I had to get home. My batteries seem fine at those temps, as are my hub motor (I carry a digital laser thermometer) but my controller will shut down when it hits 124 degrees F. But after 5 minutes she is good to go again. 3.3 volts to 3.4 voltes seems very low to me.
How do you connect the cycle analyst to the 4000li controller???