2 batteries in parallel.........

Seeing my new batteries have arrived I feel a bit more confident about going slightly longer distances without the fear of actually having to pedal the sherman home if the battery runs out of juice.

So..... what to do...... strap a battery on the rear carrier and swap them over en-route? Possible, but for the cost of a couple of audio XLR connectors and a length of 13amp twin and earth I thought I'd go down this route and give it a test run to see if it's a success.....





It's a bit string and sellotape at the moment but good enough for test purposes. "What is it?" I hear some of you ask........ it's two batteries running in parallel which essentially doubles the capacity (amp hours) whilst maintaining the original voltage...... My guess is this will not only extend the range but it will make serious hills a lot less demanding and she shouldn't redline as there is more juice on tap to cope with demand.

Naturally there's more "weight" with another battery strapped on the rear carrier but that would be there "anyway" if you were going to go down the other route of en route refuelling...... we could even be more perverse and add a third, a fourth or even a fifth battery and connect them all in parallel.... or we could connect a couple in series and break the land speed record (erm.... let's stick to parallel for the time being!) there is so much potential with these bikes.

I'm surprised Ezee chose a 3 pin audio XLR connector as a power connector..... perfectly good but a simple 2 pin dedicated DC connector would have sufficed.... it also amazes me in the audio world how many manufacturers use the wrong type of connector for the job (ie: a 75 0hm bayonet locking connector for DC duty) anyways.... again, rambling!

I've had a look inside one of the phylion batteries and it'll be pretty simple to make one up in a housing "purpose built" for permanent fixture to the rear carrier with a fixed lead terminated with an XLR plug to hook into the stock battery..... a lot lighter than the stock battery too (and that includes the Sanyo!) I won't say anymore on this until I have built my prototype and fully tested it...... running about with a stock phylion strapped onto the rear carrier is far from ideal...... the idea I have is to extend the rear carrier and fit the semi permanent (ie can be removed and replaced when necessary) battery pack "under" the carrier so you can still fit knogs, panniers etc. etc..... It's also simple to knock up a battery charger for a few quid, I'll upload the DIY details so anyone competent with a soldering iron can make one should they wish.

Quite a lot of thinking going on here at the moment....... along the lines of £300 for a fekkin battery and £75 for a charger you gotta be insane mate! kind of thing but even more thought into maxing the range of these guys to the hilt without resorting to onboard windmills, solar panels and fit people!

This is NOT rocket science it's essentially a motor and a battery...... thing is you can make a motor zoom with voltage but you'll soon drain the batteries...... the brief I have set myself is to get a realistic 80 mile range (on the 15.6mph cut out of the motor setting) with moderate pedalling.... (when I say "moderate" I'm basically saying just rotate the pedals with your legs in a circular motion.... ie: follow them round the dial!)

Jesus..... I don't half waffle eh? My next post on this will be the "proof of the pudding" warts and all full "under the bonnet" type of thing...... it's not only "doable" it's a walk in the park for me and WILL materialize in a couple of weeks..... being banned from "driving" was the best thing that ever happened to me....... seriously!
 
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Sorry.... forgot to mention...... if you want to try this tweak you'll need two "audio grade" XLR plugs and a length of twin and earth..... once you have soldered shove those puppies in a vice and flood in some epoxy resin (araldite)...... helps with mechanical integrity and prevents moisture ingress / oxidisation blah blah.................



 

Django

Esteemed Pedelecer
Feb 11, 2007
453
1
Crikey, does that seat go any higher - methinks a step ladder is in order? :D

Cheers,

Django
 

Footie

Esteemed Pedelecer
Jun 16, 2007
549
10
Cornwall. PL27
I don't have an anorak and why would you want to put a tent over your bike :confused:

Anyway, where did you get your rack? Or did it come with the bike?
That's a good solid rack. Far better than the silly seat post mounted thing I have on my MTB.
.
 
Crikey, does that seat go any higher - methinks a step ladder is in order? :D

Cheers,

Django
She's pretty much maxed out at the moment and still not optimal.... the "manager" at 50 cycles , Scott, assured me he was the same height as me six foot four inches and the bike was perfectly sized for him etc..... BULLSHIT! It's a longer stem than stock and does still go a good 4 inches into the stem so shouldnt snap off.
 
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fishingpaul

Esteemed Pedelecer
Sep 24, 2007
874
86
I think inside leg size is far more accurate than height, two people of equal height could require very different frame sizes,due to longer or shorter legs.
 

Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
Pinkie,

Good morning, how are you this fine morning?

If you parallel up batteries, you should use a pair of diodes (Schottky are best), unless the batteries are the same type and you can be sure they are always at the same state of charge. There's been a few threads on this on the forum, James has done it and so have I.

Nick
 

aaannndddyyy

Esteemed Pedelecer
Jun 7, 2007
304
9
63
Norwich Norfolk
Be carful extending the seat that far out of the frame if the saddle steam is not far enough into the down tube the strain on the upper part of the down tube could curse it to snap.
 
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Nov 10, 2006
178
14
Midlands
Have a look in CPC. You can get flush right-angle xlr connectors that won`t stick out like sore... xlr connectors

 

john

Esteemed Pedelecer
Nov 1, 2007
531
0
Manchester
I'm surprised Ezee chose a 3 pin audio XLR connector as a power connector..... perfectly good but a simple 2 pin dedicated DC connector would have sufficed....
Not sure about lithium, but on nimh batteries the third pin is used for the thermistor which tells the charger when to stop.
 

john

Esteemed Pedelecer
Nov 1, 2007
531
0
Manchester
Sorry.... forgot to mention...... if you want to try this tweak you'll need two "audio grade" XLR plugs and a length of twin and earth.....
You might want to check the cables from the XLR socket to the cells as it will be designed for charging current rather than motor current.
 

Haku

Esteemed Pedelecer
Jun 20, 2007
339
4
Gloucestershire
I don't have an anorak and why would you want to put a tent over your bike :confused:
*cough*pitching a tent*cough* :D


I haven't actually drained my new lithium-ion battery to 'empty' level yet as my journeys aren't long enough between charges and it's still too bloody cold to just go riding long distances for the fun of it - global warming yeah right ;), but one day I would like a 2nd battery so I can go on longer journeys as the hills round here really take it out on the battery.
The Urban Mover guy said something about it happening or being a possibility for the UM bikes by using a jump-lead, oddly the connector on their new Panasonic lithium-ions has 5 pins but only two are used (I peeked inside the top of the battery pack).
 

Ian

Esteemed Pedelecer
Apr 1, 2007
1,333
0
Leicester LE4, UK.
I'll be surprised if that cable between the charging sockets is actually does anything as the sockets are not connected directly to the cells, instead being the input to the batteries internal BMS charging circuit.
 

aaannndddyyy

Esteemed Pedelecer
Jun 7, 2007
304
9
63
Norwich Norfolk
I did a similar set up with NiMH batteries, but in series to give 48 volt had to make another hole in the case and put a male XLR connector in connected to the main live wire.
 
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