Nano batteries with Tongxin

[Dadplus2]

Do it like this and you'll be able to adjust the amount of boost with the pot. Leave off the throttle and substitute a latching push-to-make switch. It's not easy holding a "boost" button for a long time. I'd use at least one brake switch. Get one of those cheapo bike computers off Ebay (about £2); Cut off the sensor at the computer end; Fix the spoke magnet to your brake cable where it runs along the cross-bar; Tie-wrap the sensor to your frame. Now you have a brake switch that allows you to keep your nice brake levers.- if that's why you don't want brake switches.

Sounds interesting have you actually seen a practical application of this kind of switch/pot on a bike?

 

[Deleted member 4366]

i have them on both my main bikes and use them as a cruise control

 

[Dadplus2]

OK I think I understand, forgive me though I am not electrically minded I'm the fool that can do it for a pound. Question: So the pot kind of takes the place of a throttle?

You push the 'switch to make' motor has power and off you go, then adjust the amount of power to the hub via the pot switch.

Then you want to stop pull brake, power is cut, then when you release the brake is the system armed/live again? That bit must be wrong.

 

[Deleted member 4366]

OK I think I understand, forgive me though I am not electrically minded I'm the fool that can do it for a pound. Question: So the pot kind of takes the place of a throttle?

You push the 'switch to make' motor has power and off you go, then adjust the amount of power to the hub via the pot switch.

Then you want to stop pull brake, power is cut, then when you release the brake is the system armed/live again? That bit must be wrong.

The pot works the same as the throttle, but you can leave it in any position to dial in the amount of power you want to cruise at. The switch switches between the throttle and the pot, so you can use either, but not both at the same time. The pedal sensor operation is unaffected and it's overridden by whichever throttle you've chosen, so I used a three position switch, where the middle position connects neither the throttle nor the pot.
When cruising with the pot, the motor is cut when you operate either brake. This quite good when set at low power. As you've figured out, as soon as you let go the brake, the motor makes power again. Naturally, this doesn't work so well if you've selected a lot of power, bearing in mind these motors can give over 1KW

 

[NRG]

.... The pedal sensor operation is unaffected and it's overridden by whichever throttle you've chosen, ....

That will depend on the controller though d8veh, with the Xeicheng 116 based controllers the pedelec overrides the throttle so you would have to disconnect it...

 

[Dadplus2]

I still may try push button control to keep is simple but am looking at Hall Effect Push Buttons does anyone have any comments on these types of switches.

Hall effect linear sprung return

Or Hall effect momentary I suspect this is just a push switch for hars environments ie uses magnetic fiels instead of contacts?

 

[Dadplus2]

I've got part one completed now with the bike built and tested. Its around 9kg at the moment and the reason I mention this is that, its amazing how different it feels to ride.

Once you take off the gears and all the other stuff it seems to go up hills so much easier. I had always thought that it was pointless having a light bike if you could just go on a diet and loose a few pounds and it would be the same. Seems not though.

I am therefore hoping that will translate into an electric bike with different characteristics taking less power to move forward and up, leading to less stress on the motor and battery.

Waiting for my bits to turn up before I can get cracking.

 

[oigoi]

I built a similar bike myself once and a bit like you have done, just stripped away as many bits as possible to save weight. 9kg is quite impressive if you can get the ebike conversion under 5kg you have a 14kg ebike

 

[Dadplus2]

I've added up the weight of the bits and it should come to just under 4kg so I am aiming to get under 13kg for the project. Hopefully I will get some progress up next week.

 

[flecc]

Once you take off the gears and all the other stuff it seems to go up hills so much easier. I had always thought that it was pointless having a light bike if you could just go on a diet and loose a few pounds and it would be the same. Seems not though.

Yes, it's not the same thing at all. The reason is that within any age band, the body automatically adjusts the muscle strength to accurately match the body mass, so long as that mass is within normal bounds and not at obese level. The mechanism is that normal living movements with a body weight applies the right amount of exercise relative to that weight to keep the muscles fit and suitable.

Therefore plus or minus a few kilos of body weight makes no difference to personal performance, while plus or minus bike kilos does make a real difference.

I think you are on the right lines to create an e-bike that's nicer to ride.
.

 

[amigafan2003]

My four 5000mah 6s lipos, charger, psu, paraboard and cables have landed in the UK

Just have to wait for them to clear customs

 

[Scottyf]

What you got for if you don't mind me asking?

 

[amigafan2003]

I Ordered:-

Turnigy A-6-10 200W Balance charger
Turnigy T-20Pro Quality 16A Power Supply
EC3 Battery Harness 14AWG for 2 Packs in Series
2x EC3 Battery Harness 14AWG for 2 Packs in Parallel
EC3 plugs (10pairs/set)
Hobby King Battery Monitor 6S
4x ZIPPY Flightmax 5000mAh 6S1P 15C 4
Parallel charging Board for 6 packs 2~6S

£205 inc del.

 

[Dadplus2]

That's a pretty powerful pack, what kind of range do you think it will give? I've only ordered x2 5s 4000ah packs but am hoping for around 20miles assisted

 

[amigafan2003]

Assuming 20 watts per mile at 20mph it should be around 18 miles range throttle only, allowing for a max 80% discharge.

I calculate your pack to give you 7miles range - that's just throttle though - obviously you'll get more than that if you peddle as well.

 

[Scottyf]

I use about 7amp hrs using a 10amp pack for 21miles with pedalling. But that's using alot of throttle.

I did use a 5 amP pack to do a 18mile round trip but only ever used the throttle sparingly on hills etc.

Least with the smaller batteries you can always add a couple more if you need more range!

 

[Dadplus2]

I guess range is subjective when potentially so many factors are involved. The only true measure must be an average speed throttle only on a flat run. Following on from earlier in this thread I wonder whether a lighter bike will have a significant increase in range. I think I will have to invest in a cycle analyst even though they are quite expensive.

My batteries are going onto a plane in Singapore.

 

[Dadplus2]

All the bits have finally arrived - thanks Alan for the hub and wheel etc. The batteries won't fit into the expensive Camelpak bottle so I've got an aluminium one now and cut the top off it.

Really nervous now though as the batteries come with next to useless plugs on the end and won't even plug into the Turnigy charger. I have to cut them off and solder on some EC3 plugs all new to me. Thanks Amigafan2003 I pretty much copied your list of supplies.

So assuming I can get the plugs on and charge the batteries worried I'll do it wrong, the plan was to connect the batteries in series and then charge them using one of the two balance plugs. No idea which one so I may just charge them separately on the balance board for now.

Then its the wiring up, probably straightforward as the (unknown controller) is prewired with Anderson connectors, I may ditch these as the are pretty fat and would need waterproofing.

Lots of fingers crossed!

 

[Scottyf]

Most chargers are only good for 6 series rc lipos.
So the above method won't work.

What you can do is the following.

Any battery you parallel you can join up. Eg
Two 6s lipo 5000mah batteries.

You can join both larger wires positive and negative.
Then you can solder each of the 7 balancing wires together.
This way instead of a 6s 5000mah battery you have one larger 6s 10000mah with balance wires to charge using a normal lipo charger.

But that's what para board effectively do without soldering. But the solder is a more permanent connection.

 

[amigafan2003]

@dadplus2 - when you're putting on the new connectors only do one wire at a time - you don't want two bare wires from the battery pack to touch!

have you got a good soldering iron? Have you done any soldering before?