Panasonic System Power Delivery Explanation

flecc

Member
Oct 25, 2006
52,807
30,379
I'm sure you'll see a big benefit in using them in parallel rather than individually, overall better performance and more range.
.
 

tangent

Esteemed Pedelecer
Mar 7, 2010
299
0
I think so as well Flecc. By bench testing I hope to put a number to "Big benefit". Just ordered one of those Turnigy Watt Meter things to help me out. Should be less tedious than taking readings for hours on end and plotting graphs.

This is a fantastic forum, which I discovered it years ago.
 

Genesis750

Pedelecer
Oct 22, 2010
37
0
Panasonic 26v

So now I've bought a Kalkhoff. Why is the battery 26v? Most systems seem to be multiples of 12v - 12, 24, 36, 48v. What happens if I connect up (for example) four 7.4v LiPo batteries in parallel to give 29.6v? these can be found at approx £30 ea on ebay for 5Ah*7.4v and would extend my range if connected in series to the existing 26v 10Ahr - or would avoid fully discharging at least. I am presuming its not that simple and somewhere I would either blow my expensive system or burn something down?

Yes I appreciate I would probably have to split the 7.4v's down for charging which could prove to be a right pain.
 

flecc

Member
Oct 25, 2006
52,807
30,379
The reason for the nominal voltages of 26 and 37 volts with lithium, rather than the 24 and 36 volts normally encountered, is the cell voltage, nominally 3.7 volts with most lithium types. Therefore 7 cells makes 25.9 volts, ten cells makes 37 volts.

Other battery chemistries have cell voltages of 1.2 (NiCad and NiMh) and 2 volts (lead-acid), both multiplying to 12, 24 or 36 volts etc.

Higher voltages carry risks with your bike since the supply powers a complex computer-like 5 volt mainboard inside, which might not take kindly to over-volting:

 

Lloyd

Pedelecer
Jan 22, 2010
166
0
If you want to increase range then you need to increase the capacity of the battery not the voltage. The voltage will increase power and as Flecc suggests you will destroy your controller.

The other problem with the 7.4v lipo's is they are 2 cell packs designed for rc cars, of which their esc (effectively the same as an ebike controller) is designed to limited the cells minimum discharge value (typically 3v/cell for Lipo). The bms of a panasonic battery is somewhat different, so there wouldn't be that failsafe mechanism to protect the battery from negative discharge below 3v/cell if using individual packs.

Basically if you want to increase range you should keep it at 26v, but increase capacity, such as using the new 12 or 18Ah battery packs.

I hope that is of some help!
 

asauter

Just Joined
Jan 19, 2012
1
0
Hi Guys First post.

I am trying to add throttle control to the eneloop panasonic (originally sanyo).

I have seen the excellent thread characterizing the throttle response and the applicable regulations. I am interested in controlling the throttle electronically.

The torque sensor in the crackset is read by 1) applying an oscillation signal and 2) reading the resulting waveform in firmware. The total change in this signal is very small (<3% tau). If the signal exceeds certain limits the device goes into an error mode and all 3 leds blink. But if the signal is close I think you only get one blink.

Does anyone know how to add external throttle, to this device, or any company that does? If I understand there is a feature for walking your bike up a hill by third party is it biketech?

It looks like a impressively precise sensor, any information on how it operates, made, or how to control it would be greatly appreciated.

Regards
as
 

flecc

Member
Oct 25, 2006
52,807
30,379
The ex-Sanyo Eneloop system isn't related to the Panasonic unit of this thread of course, so any information from that may not apply. However, it's suspected that the variable resistance "walk-alongside" throttle of the Panasonic unit isn't related to the pedelec unit, but is created by connection to a logic level output on the mainboard to simulate a "pedals-are-turning" signal. It only operates at minimum power so is not very useful, even as a walk alongside throttle. It was indeed originally created by BikeTec, but now adopted by Panansonic as an option.

The thumb throttle is a 10k potentiometer with only part of the range used, throttle off 1.3k, throttle full on 2.5k, giving a 1.2k operating range.
.
 
Last edited:

nowthenpal

Finding my (electric) wheels
Feb 7, 2013
10
0
I'm a first timer on here too. I have the Giant laFree with the panasonic system and I too would love to fit a throttle to it, just because I'm a lazy rider after a couple of years on my powabyke. The Giant is a lovely bike but sometimes I just be bothered to pedal. I've searched a few sites on the net and come across this one in my search for adding the throttle. Any ideas please?
many thanks Stephen.
 

flecc

Member
Oct 25, 2006
52,807
30,379
It can't be done Stephen, the system is strictly controlled only by the pedelec function. The internal electronics are fully encapsulated and sealed into the right hand crankcase, this alone making investigation almost impossible.
 

nowthenpal

Finding my (electric) wheels
Feb 7, 2013
10
0
Thanks flecc, saves any further searching. I'm gutted really because my laFree is a lovely bike, I'm now thinking of taking my front wheel and electric off my powabyke and adding them to the Giant, sounds bizarre, I know, but then I'd have the pedal power of the panasonic system and the front hub power on the throttle! Ha ha.
many thanks again for your reply.
Stephen.
 

flecc

Member
Oct 25, 2006
52,807
30,379
Not crazy Stephen a few have done that. The Lafree version below with a Heinzmann front motor is doubly cheeky since it also has a tiny petrol generator on the carrier! Of course double 250 watt motor e-bikes aren't legal, but not likely to be spotted:

 

nowthenpal

Finding my (electric) wheels
Feb 7, 2013
10
0
wow, now that is what I was thinking about! Its kept me awake tonight. I'll get some pictures posted in the morning so you can see my project in the workings.
 

flecc

Member
Oct 25, 2006
52,807
30,379
Thanks for that Stephen. Watch out for the fork drop-outs on the Lafree, the alloy material in those and the frames is surprisingly soft on some of them. Adding a powerful front motor like the Powabyke one really needs a torque-arm added to the spindle to prevent it turning and spreading the fork end drop-out. This is the sort of thing, goes on the spindle and is locked to the fork leg. Plenty of suppliers, CycleZee for example have a good one:

 
Last edited:

nowthenpal

Finding my (electric) wheels
Feb 7, 2013
10
0
Thanks for the advice, I was trying to add some SR Suntour suspension forks too, the roads round here are "well lets say rough", if I can't fit them, I'll look into this.
Questions now if you don't mind?
Do you know what all the cables do on my panasonic unit?002 (300x225).jpg
Also I have a back hub ready for a rebuild and I'm unsure on the wires to?004 (300x225).jpg
Sorry I keep finding more bits and pieces, this build turning into a right project here.
 

flecc

Member
Oct 25, 2006
52,807
30,379
The connectors on the Panasonic unit are for the Handlebar switch lead and the optional walk-alongside thumb lever throttle that only operates at minimum power to 3.6 mph. The third one may be either lighting and software restoration, or only the software, depending on model and age. The lighting option isn't worth using as it can only supply 6 volt filament bulbs, not LEDs which will blow.

Your hub motor connections can vary. It can have either three thickish phase wires or those plus five thinner Hall sensor wires. The appropriate controller has to be used, depending which it is.
 

nowthenpal

Finding my (electric) wheels
Feb 7, 2013
10
0
Mine has the on/off/eco switch on the bars, I did'nt know there was a optional walk-alongside thumb level throttle? It's hard to find info on this system, unless I ask you flecc! Haha, I have 6v filament lights, but they were never connected when I bought the bike, I thought I'd have to add a 6v dynamo. This software restoration sounds interesting?

The hub motor was bought off eBay sometime ago with no info other than spares or repair 24v hub motor. I have a couple of 24v motor controllers, I'm sure now I can work this unit out, if not they will be more questions?

I hope you don't mind me racking your brains for all this info? I can't thank you enough, I wish I could repay you with some of my knowledge.
many thanks Stephen.
 

flecc

Member
Oct 25, 2006
52,807
30,379
No problem Stephen. The software connection doesn't hold much interest, no opportunity to boost the power. If it has the lighting, it's derived from the 24 volts being chopped at high frequency to give a quarter of the time on, three quarters off. That chopped on signal is damped by the resistance of 6 volt bulb filaments into a roughly smoothed 6 volts. That's why LEDs would blow, they would be fast enough to see the full 24 volts narrow pulses.

I'm not an expert on controllers but some in here know many of them so may be able to help if you are able to give some identification or photos of the ones you have. Sorting the controller to motor wiring is a bit trial and error since Chinese colour codes are often variable.
 

nowthenpal

Finding my (electric) wheels
Feb 7, 2013
10
0
For sale, Giant laFree with this pedelec system, I've tried my hardest to get it to work, first 100 pound can have the whole bike.
 

D8ve

Esteemed Pedelecer
Jan 30, 2013
2,142
1,294
Bristol
Have you sold this?
I am looking for a 36volt Panasonic battery case to build up a replacement battery for my bike.
D8ave
 

Advertisers