Duct Tape E-Bay Lifepo4s???

[Freddyflatfoot]

Ping has let me know that my pack has been posted. Got a tracking number, which I have checked. definitely appears legit.
Looking forward to recieving my pack soon! Very impressed with Mr Ping.

 

[geoff57]

Ping has let me know that my pack has been posted. Got a tracking number, which I have checked. definitely appears legit.
Looking forward to recieving my pack soon! Very impressed with Mr Ping.

hi freddy you should get your pack in about 6 days if they take as long as they took with me. Once it has left shanghai start looking on the shipping web site for your country, the EMS tracking was still saying dispatch from sorting center when I recived a knock on the door with a package from ping for me.

below is a copy of the tracking on my battery, should give you an idea of how quick it will come.

　
Timing Site Status
　 2008-02-02 16:47:00 PUDONG Posting
　 2008-02-02 16:52:00 210 Despatch from Sorting Center
　 2008-02-02 22:39:21 SHANGHAI Arrival at Sorting Center
　 2008-02-03 00:12:26 SHANGHAI Despatch from Sorting Center
　 2008-02-05 23:33:00 UNITED KINGDOM COVENTRY PF Arrival at Sorting Center
　 2008-02-05 23:41:00 UNITED KINGDOM COVENTRY PF Released from Customs
　 2008-02-06 12:00:00 UNITED KINGDOM O22442 Delivery

good luck

 

[Jeremy Harris]

Does anyone have a direct email for Ping that works, please?

I've tried twice to email him via Ebay over the past week or so and haven't had a reply yet. I know it's been the Chinese New Year, but it seems he's been corresponding with you guys over this time. My guess is that my messages aren't getting through to him.

Jeremy

 

[SniperGaulois]

still with the battery from Anna, have managed to go for a long ride, and happy to report fantastic performance, the 48 V battery was about 54 out of the box, and after taking about 10ah it's only gone down to 52 according to the cycle analyst, have to say that the battery seems to stay very cool, whereas the controller was hot, exactly 40° after about 20 minutes of full throttle.
I checked out biscuit tins and cake tins and bread boxes to find something the right size, and there is some pretty good stuff available, but it turns out that 1 mm aluminium is very strong as long as the corners are bent at 90°, and it's very easy to bend, so have made a really nice case.

for those that are finding that the BMS shorts at about 30, you could try putting a resistor onto the throttle on the sensor cable, somewhere in between 70k and 200k will take the maximum throttle level down by 30% off

 

[Freddyflatfoot]

still with the battery from Anna, have managed to go for a long ride, and happy to report fantastic performance, the 48 V battery was about 54 out of the box, and after taking about 10ah it's only gone down to 52 according to the cycle analyst, have to say that the battery seems to stay very cool, whereas the controller was hot, exactly 40° after about 20 minutes of full throttle.

Glad go hear your pack is going well. what amperage are you drawing to get the controller hot? Your controller probably got hot on other battery chemistries as well, as that would be a function of current draw.
I'm not expecting any problems, as my controller is limited to 15 A.

 

[SniperGaulois]

it's a 20amp controller, I hadn't really noticed it getting hot before because the current battery is 53v compared to 35v previously, and I have a new bag which is waterproof with pretty thick nylon which keeps it warm as toast.

 

[kbarrett]

Hi All,

I have a question is possible to connect (2) Ping pack in parallel, to have a better cut of amps rates ?

Thank you and have a nice day!
Bikeraider

Parallel is OK, yes. Ping can make you a pack to order ... you can just ask him for a bigger one at the same voltage ... he just about makes them to order ( longer turn-around time, of course ).

Avoid putting Ping packs in series.

 

[kbarrett]

Hi Kbarrett,

I already have, a 48 Volt 20 Ah pack, so i try got a new one, and i just like to know if is ok to connect both in parallel.

Thanks good day!
Bikeraider

I would guess that it would be OK, provided voltage and amperage matched.

If you are worried buy a schottky diode and isolate the packs from each other.

 

[albie]

if you connect the packs in series ... is there a diode which can isolate them (ala shiotsky diode)??

 

[mazott]

Schottky diodes would do when the packs in parallel, I believe.

 

[albie]

Schottky diodes would do when the packs in parallel, I believe.

thats it... now is there a diode similar to that for packs in series... thats what i was asking.

 

[mazott]

The LVC voltage level should be adequate for the right battery chemistry perhaps. I recall the LVC in the Crystalyte 48V/20A controller is 29V. My question boils down to the following: Will 29V be still high enough to set a safe LVC for a 48V LifePO4 pack? Actual terms valid for 48V controller owners of course.
Also, routinely swapping in and out a BMS is not presumably as simple as placing a diode in the middle, posing the likely problem of finding a suitable switch to get it practically easy. Just my thoughts.

 

[kbarrett]

if you connect the packs in series ... is there a diode which can isolate them (ala shiotsky diode)??

No ... sorry. The purpose of a schottky diode is to prevent two packs in parallel from effecting each other.

If you put batteries in series, you have done the exact opposite of isolating them.

Ping has already stated that his BMS won't handle packs put in series ... if you insist on doing that, you will need to remove the BMS's from both packs while you have them in series ( and you will need to install connectors yourself in order to do this ).

 

[kbarrett]

Hey Guys,

I just receive this email from Ping's very intersting.

OK then ... that's the word.

If you want to parallel, get a schottky, and BTW, your warranty is now void.

 

[Link]

Ping has already stated that his BMS won't handle packs put in series ... if you insist on doing that, you will need to remove the BMS's from both packs while you have them in series ( and you will need to install connectors yourself in order to do this ).

What about for 36V packs, though? If the BMS can handle up to 100V, then shouldn't even the fully charged voltage of a 72V be fine with his BMS? Or does he use a lower voltage one for the 36V packs?

Warranty whatever. If it blows, oh well, I guess.

 

[kbarrett]

His old BMS nuked itself at 36V at 35 Amps.

I don't think his new ones are all that much better.

Increase the voltage, and it will take less Amps to fry the sucker.

Watts ( 36V at 35 Amps ) = Watts ( 72V at 17.5 Amps )*


*I think ... it's been a while since 2nd year Physics ....

 

[Link]

His old BMS nuked itself at 36V at 35 Amps.

I don't think his new ones are all that much better.

What fries? The FETs, microcontrollers, or what?

 

[kbarrett]

BTW Kbarrett I think my English is better than your French, my reading is may be hard to read but I think everyone is able to read me here and they know what I'm try to say!

Good day!
Bikeraider!

I'm sorry, but did I offend? That was not my intention. If I did, then I apologize.

Yes, your English is just fine, and my French is non-existent.

 

[kbarrett]

His old BMS nuked itself at 36V at 35 Amps.

I don't think his new ones are all that much better.

What fries? The FETs, microcontrollers, or what?

The FETs. See page thirteen of this monster thread.

http://endless-sphere.com/forums/viewtopic.php?p=46537#p46537

 

[Link]

Ah, should be an easy fix then.

I need to know because I'm really close to getting a 36V 10Ah pack from Ping. I wan't to be able to switch two of them (via relay) from parallel to series. This will allow me to (eventually) have four speeds on my bike.

Dual-motor twin-pack bike...8)

 

[kbarrett]

Ah, should be an easy fix then.

I need to know because I'm really close to getting a 36V 10Ah pack from Ping. I wan't to be able to switch two of them (via relay) from parallel to series. This will allow me to (eventually) have four speeds on my bike.

Dual-motor twin-pack bike...8)

I think the easiest route would be to bypass the BMS completely in series, and take Ping's advice and Schottky them while in parallel.

Might need some creative wiring to do that with relay switches, but it should be possible.

These are really great packs ... 26 miles hauling my fat ass with his 36v18A and I couldn't get to the bottom of it. I don't think I could stand riding long enough to drain out two of these packs in parallel.

 

[kbarrett]

The Schottky's at ebike.ca are rated for peak load ... not battery life.

Your batteries are ( I assume ) 20AH ... 20 Amp Hours. This is a measurement of how much current total you can draw out of them.

Those Schottky's are rated 25A and 40A instantaneous load ... like a fuse, or your controller ( a really spendy fuse ... heh ... ) would be rated. Get the schottky that matches or exceeds the expected highest instantaneous load ... if your Controller is rated at 35A, then get the 40A schottky. If your controller is rated at 20A max, then get the 25A schottky.

BTW ... you CAN connect Ping's packs in parallel with the BMS in use ... as long as you isolate the packs with a Schottky diode.

 

[Link]

I think the easiest route would be to bypass the BMS completely in series, and take Ping's advice and Schottky them while in parallel.

Might need some creative wiring to do that with relay switches, but it should be possible.

These are really great packs ... 26 miles hauling my fat ass with his 36v18A and I couldn't get to the bottom of it. I don't think I could stand riding long enough to drain out two of these packs in parallel.

I'm pretty sure I could do it, given enough relays.

Technical question: Factoring in cost, reliability, and size, should I go with a regular solenoid relay or a solid-state?

Still might need a few DT/DP relays, though.

26mi? Daaaaaaaaamn. I should get killer range in parallel batts/parallel motor mode. Should top out at ~18mph in that mode in a 20" rim. And imigine the torque at 40A in series.

I probably won't use it much, but I'll have a parallel battery/series motor gear. Only about 10mph in that mode. Range? Too far to test...

Series battery/parallel motor should get me to just over 35mph 8).

 

[Arbiker501]

HEllo guys,

I just got a Email from PIng.. Mostly wanted everyone to know on the forum he was sorry he has not emailed you back.. That he has been gone but will try to catch up and please be understand.

Thanks

Arbiker

 

[Link]

Keep selling those packs and all is forgiven !