E-S Stealth Electric Bike Owners

[biknut]

Hi!
I Have those battery's but they are 25C/50C
View attachment 1
I Maked a harness for them when I was testing them in my bomber
View attachment 2
You will need a good charger if you want to charge and balance them at the same time. I use a Hyperion 1420i, they are about 150USD
You will have to split the pack back to 37V again when you charge and balance the 1420i cannot handle 20s, maximum is 14s
I usually charge them 4 in parallel, so I maked a harness for the main leads and harnesses for the balance leads.

Man what a hassle! I will never go back to this
You really don't need BMS but you have to monitor them carefully if you do not do this you will shorten the lifespan and in worst case they will explode
But to make it short. The batterys were garbage, they where sagging a lot, at WOT, voltage dropped below 69V. After test ride they were pretty darn hot.And this was a configuration of 10Ah74V(4 packs in total) so it is equal to 250A if we count with 25C (2packs*5Ah*25C)
So those 25C figures does not mean shit. I would guess they are more to a 5C figure

So to conclude, I would buy batterys with more juice, but would I hassle with all disconnecting, those connectors, chargers, balancing, nah, not worth the extra mileage for me

Thanks for sharing your valuable experience Allex. It sounds more and more like using the 65c battery is the only way to go. Whether it's even worth it is the question. That's one reason why I'm thinking to make only a 5 ah so I can test one out without breaking the bank so to speak. So far I haven't seen where anyone tried using a 65c. If that kind doesn't work well, then I'll cross them all off the list.

I think maybe the real problem with these Nano battery's is they're meant for small light weight rc vehicles that don't draw the kind of sustained high current that Bomber's are capable of.

 

[Kepler]

To be honest, I am not keen on trying to promote LiPo for ebike applications either not because they may puff up or that they may only last 200 charges but mainly due to their inherent dangers.

Go 18650 if you can. Problem is that even the best 18650 cells only have a 2C rating so the pack needs to be big if you are going to pull any decent amps. And with any battery chemistry, run them at their rated C rating or above, and watch how quickly you stuff them.

Cell_man does some of the best packs around. Perhaps 2 of these packs in series might be the go http://em3ev.com/store/index.php?route=product/product&path=35&product_id=160

$600 bucks plus chargers plus shipping and it is yours. And for that you get a max of 20A discharge so not even close to what a Bomber sips.

 

[rp3]

I've found my 3.7AH Compact packs will only give 3AH from 4.2V down to 3.4V, which probably means either the 3.7AH rating is a flat out lie, or they are draining down to 0V when capacity testing.

80% of 3.7 is 2.96. Sounds like they are doing fine. :wink:

 

[Rix]

I think some of the folks here are being a little hard on the Lipos. My Pops machine is powered by the Hyena Neutron Kit running 12s 15Ah pack. He bulk charges to 50V (4.167 Volts per cell) and balences the cells to 50.4 which comes out to 4.2volts per cell. Total capacity is 750wh, my dad never discharges past 630Wh or allows the pac to go below 42 volts. When bulk charging, he does monitor the cells though. My dad has had this set up since May of last year, during the warmer months he is riding alot requiring to or three charges a day. He hit 200 cycles back in December, I don't know where he is at now. Not a single problem with it. But because he is only pulling 2.5c, there is no volt sag at all. The pack settles after balencing to about 49.8v or so. Anyway Lipos can be set up to be almost as user friendly as other packs, but no matter what, they do require a little more attention but not something I wouldn't hesitate with. I was really lucky to spend the day with Hyena and pic his brain on lipo charging and maintenance. I believe learning to use Lipos in Ebikes is best done by having someone knowledgible go over the dos and donts with you in person.

Rick

 

[Rix]

CD,

I have never seen a LiPo that meets its rating. Just take it for granted that you will get about 85% of the rated capacity. I get about 5 ah out of the 5.8 zippy compacts. Most of my bikes only pull about 2C so no problems with puffing so far. I do have plenty of puffed LiPo's in my collection though

Theo V, what Kep said about Lipo C rating not meeting its rating is spot on. I was talking with Jones CG a awhile back, he provided me with his guidelines on C rating and told me the following involving 40C 5Ah cells: 40C means you can pull a maximum of 200 A per 5 Ah cell. Which is nuts, and not recommended However, I treat these figures with suspicion. As a general rule, take the quoted C rate, halve it, and make this your maximum. Then halve it again for your continuous use rate. So the 40C cels are good for 20C max, and 10C continuous. Which for a 20 Ah pack is still 200 A.

These figures can be applied to 20c or 30C or any C rated Lipo pack out there. Being that our stock controllers are limited to 65-70, your spare 20s 11.6Ah (10s 5.8Ah banks seriesed and paralled twice pack you want will work more than fine on the Bomber as a back up.

Rick

 

[QuietRush]

Looks like some one in South Australia might do well to go pay this guy a visit, 2nd hand Bomber with Quigley side covers:
http://www.gumtree.com.au/s-ad/glandore/other-motorcycles-scooters/stealth-bomber/1035922667

Looks well set up. Interesting bar choice.

 

[Rix]

Out of the MTB Action mag, Feb 2014 issue

Ft, I missed this earlier, these articles are a double edge sword. On the leading edge, this kind of publicity is great for Stealth and getting the word out about the most awesome production kick ass Ebike and company on the planet. However, on the trailing edge, this kind of public awareness also will get us Stealth riders spotted easier on MTB only trails, which I ride alot of around Tahoe and Bogus up in Boise. Be that as it may, riding smart and pedaling when everyone is looking will not inhibit us.

Quigley, once again, nice Bomber with the QMS treatment. As usual, looks nice, and tougher than Spartan having a bad day at a pawn shop.

 

[biknut]

CD,

I have never seen a LiPo that meets its rating. Just take it for granted that you will get about 85% of the rated capacity. I get about 5 ah out of the 5.8 zippy compacts. Most of my bikes only pull about 2C so no problems with puffing so far. I do have plenty of puffed LiPo's in my collection though

Theo V, what Kep said about Lipo C rating not meeting its rating is spot on. I was talking with Jones CG a awhile back, he provided me with his guidelines on C rating and told me the following involving 40C 5Ah cells: 40C means you can pull a maximum of 200 A per 5 Ah cell. Which is nuts, and not recommended However, I treat these figures with suspicion. As a general rule, take the quoted C rate, halve it, and make this your maximum. Then halve it again for your continuous use rate. So the 40C cels are good for 20C max, and 10C continuous. Which for a 20 Ah pack is still 200 A.

These figures can be applied to 20c or 30C or any C rated Lipo pack out there. Being that our stock controllers are limited to 65-70, your spare 20s 11.6Ah (10s 5.8Ah banks seriesed and paralled twice pack you want will work more than fine on the Bomber as a back up.

Rick

I think your estimates sound reasonable based on everyone's experience with these kind of battery's. I'll stick with my original plan, and buy 2 of these 5 ah baddest ass 65c Nano's, and hope for the best. Even halving all the values that's still well over any demands a stock Bomber should be able to put on them. Maybe 20% over. A 5 ah pack should allow me to test them at full throttle for at least 3-4 miles a charge. In the event these battery's would prove to be able to handle that kind of abuse, a 20 ah pack would only cost about $1500, which is a lot less than a stock 18 ah battery. According to my calculations though, 8 of them won't fit in the stock battery box, but probably 6 will. In my case I doubt that matters much though, because I wouldn't be happy with even 20 ah. I'll need at least 30 ah anyway, so there's always going to be some battery's hanging off the outside of my bike somewhere until technology catches up with my demands.

 

[Allex]

TV I just got a quote from Cell_man

For about the same amount of dollars you can have:
Samsung SDI INR18650-20R cells

Config: 21S, 13P
Voltage: 75.6 nominal
Capacity 25.35 Ah
Energy 1916.46Wh
Weight 13.65Kg
Cost 1756USD
This is a huge pack that will take your for some looong rides.
This price is for the complete pack with BMS which handles 80A continues current. Plug and play solution without headaches just tuck it in the frame and go.
I will upgrade to something like that in the future when my pack will get old and saggy. Or even better. I could sell the stock pack for about the same cash..1500-1700USD and get a better pack. Win-win!

I think you will be fine with 65C cells. With hobbyking cell quality I usually calculate actual C value by dividing factory figure by 5. So in this case 65c/5 so about 13C And Pack with 5Ah times 13C will be 65Amps, this is what Bomber need. So dont worry.

 

[biknut]

TV I just got a quote from Cell_man

For about the same amount of dollars you can have:
Samsung SDI INR18650-20R cells

Config: 21S, 13P
Voltage: 75.6 nominal
Capacity 25.35 Ah
Energy 1916.46Wh
Weight 13.65Kg
Cost 1756USD
This is a huge pack that will take your for some looong rides.
This price is for the complete pack with BMS which handles 80A continues current. Plug and play solution without headaches just tuck it in the frame and go.
I will upgrade to something like that in the future when my pack will get old and saggy.

Yeah that seems like a good deal. Are you sure it will fit in the frame?

 

[Allex]

Yes I gave him the dimension of the stock one.
Actually, I could sell the stock pack for about the same cash..1500-1700USD and get a better pack. Win-win!

 

[biknut]

Yes I gave him the dimension of the stock one.
Actually, I could sell the stock pack for about the same cash..1500-1700USD and get a better pack. Win-win!

Allex, have a look at the specs for those battery's, and see if you think the discharge rating, and life cycle is what we would expect, and want.

http://www.avacom.cz/Datasheety/Samsung/INR18650-20R.pdf

 

[biknut]

Yes I gave him the dimension of the stock one.
Actually, I could sell the stock pack for about the same cash..1500-1700USD and get a better pack. Win-win!

Allex, have a look at the specs for those battery's, and see if you think the discharge rating, and life cycle is what we would expect, and want.

http://www.avacom.cz/Datasheety/Samsung/INR18650-20R.pdf

Seems like what it's saying is after 250 full cycles the battery's will be down to about 60% capacity.

 

[biknut]

http://www.avacom.cz/Datasheety/Samsung/INR18650-20R.pdf

Seems like what it's saying is after 250 full cycles the battery's will be down to about 60% capacity.[/quote]

The tech sheet says they use these battery's in power tools. My experience with battery powered power tools has been that the battery's don't last all that long before they start going downhill. Maybe the Nano's won't last any longer though.

 

[competitions]

Yes I gave him the dimension of the stock one.
Actually, I could sell the stock pack for about the same cash..1500-1700USD and get a better pack. Win-win!

Allex, have a look at the specs for those battery's, and see if you think the discharge rating, and life cycle is what we would expect, and want.

http://www.avacom.cz/Datasheety/Samsung/INR18650-20R.pdf

Seems like what it's saying is after 250 full cycles the battery's will be down to about 60% capacity.

Perhaps Allex could provide the specs to cellman and ask him his thoughts on it.

 

[Allex]

7.10 Cycle life
With standard charge and maximum continuous discharge. Capacity after 250cycles,
Capacity ≥ 1,200mAh (60% of the nominal capacity at 25°C)

Ok
Note that this statement is for Max discharge, which is 22Amps for a single cell!
We will use 13 cells in parallel, and when we hit the throttle, bomber will suck around 65Amps. So Every cell will only have to give 65/13=5Amps
So our consumption will be quite gentle on these. And this, of course, prolongs their cycles and life. And the more you parallel the more you relieve the cell from stress. So paralleling is not only to get more Ah but also to prolong their life.

My nano.techs have around 100 cycles now and they give med about 3.5Ah, when they were new I could drain around 5Ah from each pack.
Same applies for all, if you push them, they will last 100-300cycles, like with powertools and one 5Ah nano-tech on a Bomber. If you are gentle, like Rix dad, you can get 500+ cycles.

And this is from cell_mans homepage(store)
Cycle Life estimated at 500-700 cycles (to 80% Retained) with 100% Charge and 100% discharge cycles. Cycle life is extended (possibly doubled) by charging to 90% and limiting discharge to 90%, so you use 80% of the available capacity (most, but not all of the time). We make it easy to control the Charge voltage with our switching charger. To accurately limit discharge the Cycle Analyst is a great tool. Using continuous High Discharge Rates over the recommended levels will cause cell heating and can shorten cycle life.

 

[parmenps]

which tire size is used on the Stealth bomber bike??

 

[Allex]

It's 24"x3" wide
http://www.jensonusa.com/Duro-Razorback-DH-24-Tire

 

[Rix]

I think your estimates sound reasonable based on everyone's experience with these kind of battery's. I'll stick with my original plan, and buy 2 of these 5 ah baddest ass 65c Nano's, and hope for the best. Even halving all the values that's still well over any demands a stock Bomber should be able to put on them. Maybe 20% over. A 5 ah pack should allow me to test them at full throttle for at least 3-4 miles a charge. In the event these battery's would prove to be able to handle that kind of abuse, a 20 ah pack would only cost about $1500, which is a lot less than a stock 18 ah battery. According to my calculations though, 8 of them won't fit in the stock battery box, but probably 6 will. In my case I doubt that matters much though, because I wouldn't be happy with even 20 ah. I'll need at least 30 ah anyway, so there's always going to be some battery's hanging off the outside of my bike somewhere until technology catches up with my demands

TV, I just want to clarify that the estimates and guidelines I have provided are from guys I have spoken with and don't want to take the credit. I speak with Kepler and Hyena the most. Along with Jones CG, those guys are the reason why know as much about lipos as I do. My original understanding of lipos was based on my RC helicopter experience. Not the same. When amperage and voltage start increasing do to series and paralleling, all sort of things start changing which I didn't really get at all. All I can say if you go to a lipo auxiliary pack, don't over discharge them and never over charge them. When charging, especially bulk charging, monitor your individual cells, especially when bulk charging. Did I mention monitoring your cells when bulk charging. if you see one of your cells going above 4.2 volts, stop charging ASAP. If you plan on only balance charging your auxiliary pack with a smart charger, not really any more risks than our current bombers provided the cells are damaged and the charger is working properly. I know I am stressing the paying attention during bulk charging lipos, its actually only super critical when you first build and use a new pack. once you have monitored your pack through a dozen or so charge cycles, and all of the cells charge up to the HVC without going over 4.2v, and you know the characteristics of your lipo pack, than you can relax, a little. For this reason when you figure out your bulk charging HVC, never go above 1.5-1.6 volts per cell. In other words for bulk charging, don't set your HVC @ 4.2 volts per cell like you can for balance smart charger.

On another note, I
Recently I posted some ride data about my 5405, and how I wasn't impressed with it. Well as I discovered, one of my Xt150 on the Phase wire from the controller had the solder come loose in the connectors bowl. it was just floating around and jiggling there. I discovered this while trouble shooting why my 5405 wasn't pulling any harder than the 5404, during my initial testing. Now that I got that blob of solder actually soldered to the Xt150 plug, the 5405 is now pulling harder than the 5404, as I expected it should have been. Top speed is still the same though at an un-assisted 39MPH hot off the charger. So now I am not disappointed like I was before with the 5405.

Rick

 

[Allex]

Nice to hear that Rick!

 

[QMS]

Out of the MTB Action mag, Feb 2014 issue

Ft, I missed this earlier, these articles are a double edge sword. On the leading edge, this kind of publicity is great for Stealth and getting the word out about the most awesome production kick ass Ebike and company on the planet. However, on the trailing edge, this kind of public awareness also will get us Stealth riders spotted easier on MTB only trails, which I ride alot of around Tahoe and Bogus up in Boise. Be that as it may, riding smart and pedaling when everyone is looking will not inhibit us.

Quigley, once again, nice Bomber with the QMS treatment. As usual, looks nice, and tougher than Spartan having a bad day at a pawn shop.

Hey Rix and QR,
Thanks mate, that Bomber is an ex demo of ours and the customer is looking at upgrading to the latest version. It's in pretty good nic as far as we know ( fitted with the latest style swing arm) and is worth looking at for anyone looking for a secondhand Bomber.
While I'm here I thought I would just give everyone in Aus a heads up that a client of ours from La Perouse Sydney NSW has recently (25/1/14) had his army green Bomber and charger stolen and he is extremely upset. It has a different seat to factory supplied along with some suction cup marks on the upper left frame section from a camera mount. Here's a pic of the stolen bike #422 and if anyone in NSW has seen it they can either contact the police,Stealth or pm me re it's whereabouts as the owner is extremely keen to retrieve it as it is only around a month old. It was stolen from a locked facility and appears to have been directly targeted.

 

[Rix]

QMS,
Checking Ebay and any out of the ordinary support quesitons on threads. These bikes are unique as they get, hopefully we can reunite the Bomber and his owner.

Rick

 

[QMS]

QMS,
Checking Ebay and any out of the ordinary support quesitons on threads. These bikes are unique as they get, hopefully we can reunite the Bomber and his owner.

Rick

The owner is also offering a reward that leads to its recovery. It is "just not acceptable" that a man (or woman) should be parted from their Stealth in this type of circumstance.

 

[remf]

It's a big city but I'll be on the lookout...on my Army Green Fighter. Unfortunately it's only a matter of time before we see a stolen bike feature in the headlines.

 

[Mueck]

Hi everyone this is my first post and I'm happy to say after a year I've ordered my new stealth bomber!! :lol:
I really wanted to know what was more value for money points against and for white brothers forks and the r ones. I always want the best gear but I've never really heard of white brothers and can find much about them in the net.... If I had the option I would have gone the bombers. But there not offering those forks anymore. How are ppl liking different forks

Thanks for your comments