Thanks for the feedback
DIY Ebikemotion Range Extender
- Thread starter James Myres
- Start date
I always appear to be late arriving at thesethreads, but this one is only two weeks cold! I’ve been everywhere trying to find how to DIY a range extender for the Gain. As we now know, the original extender is actually a battery bank which recharges the original battery, whereas Volabike’s is an additional battery that runs in parallel, reducing the wear and extending the life of the main battery, that has electronics aboard to ensure that there is not a dangerous instantaneous levelling of voltage if the two batteries aren’t almost exactly aligned (voltmeter required). This could mean fires and a total bike loss. The ’electronics’ part can be a simple resistor, but better is a Shottky diode, for around 4€, or a mosfet controller used in solar power setups, c. 45€. What I don’t know is how to make one! Volabikes battery pack and cage is 180€ on Aliexpress (yes the exact one) but the expensive part is the bespoke ebikemotion charger plug which seems only to be available if you buy 100 pieces (from China). The Volabikes extender is now on Amazon at £560. Kudos to them for putting it together, but surely the price is taking the piss? Sadly this is where we with fancy bikes are getting shafted, unlike those who use conversion kits which have many interchangeable, and cheap, parts.
Phil Agur
Member
I use a lot of Anderson Powerpoles. I have the ratchet crimper to insure even at 71 my crimping is still flawless. I could never find the charger connector so I cliped my cord a foot back and installed Anderson PP to repair it. It's only two conductors so it was simple using the 30 AMP Powerpoles I keep on hand. The challenge became where to mount the aux battery. My top tube slopes so the seat tube is short. When I try to position the battery there it hits the charge connector body. For my early testing I attached to my rear rack. I've now moved it to high on my down tube. That gives the cable room to route in a loop and connect.
SondorsMXS
Member
FYI-Likely XT60 connectors used first in the RC world (at least for me).
Phil what have you used to slow the aux battery from instantaneously equalising it’s charge with the Gain’s battery? Or do you make sure the two batteries have the same voltage when you connect Them up?
If you can build me a reliable one cheaper than the average price of $660 count me in on a group buy
Hi everyone. The range extender batteries sold for quite exorbitant sums in the EU are available direct from the manufacturers, but I can't find the unusual connector used by ebikemotion. It is clearly available from somewhere as aftermarket compatible range extenders are available. I may have missed the answer - has anyone found them? Thanks
SimonL
New Member
- Region
- United Kingdom
Another thread [somewhere else] detailed a contact made with the manufacturer because they aren't available retail. The manufacturers minimum order was either 1,000 or 10,000 units.
I've reposted this as I was mistaken on a few points. Thanks @SimonL. for the info on the connectors - I haven't managed to find that reference yet, but will keep looking.
Mahle state that charging port can be used either for charging at 2a or for an external battery at 12a. This implies that the controller board auto-senses the input and allows batteries to be connected safely in parallel or to charge the battery depending on the available current. I am assuming this is why a provider of third party range extenders has claimed parallel battery operation from what appears to be off-the-shelf batteries? Can anyone point me anywhere that sheds any light on this (ie someone whose done it?). Thanks.
Mahle state that charging port can be used either for charging at 2a or for an external battery at 12a. This implies that the controller board auto-senses the input and allows batteries to be connected safely in parallel or to charge the battery depending on the available current. I am assuming this is why a provider of third party range extenders has claimed parallel battery operation from what appears to be off-the-shelf batteries? Can anyone point me anywhere that sheds any light on this (ie someone whose done it?). Thanks.
I have also done lots of looking re people who have successfully made their own range extenders. There have been quite a number over the years. They all seem to rely on protection provided by Ebikemotion within the controller as some have just hooked up an external battery by cutting off and using the original charger cable. Several others (including your ‘third-party’) used some sort of protection for their external battery, to stop the internal battery damaging the range extender battery if the latter is connected to the former whilst having a lower voltage. There was quite a discussion on Pedelecs forum. I have been, this evening, soldering away making my own, using an ideal diode to protect the external battery (it is a very low draw blocking diode that uses a mosfet. This means that the voltage drop across the blocking diode is very very low, and virtually no heat is produced, unlike other blocking diodes). I have just connected it and everything seems fine - except the on-off switch for the extender won’t stay ‘on’ unless I keep my finger on it. I’ve obviously wired the 4 pins incorrectly (or ordered the wrong switch, one that doesn’t latch ‘on’) but have no idea what I’ve done wrong! Bah! Once I’ve sorted it I’ll post what I’ve done on my YouTube channel (Yako Rides aGain).
That's really helpful and I look forward to your upload. The connectors are indeed bespoke.
Yup I’d ordered a ‘momentary on’ not a ‘latching on’ switch. I was too impatient to wait for a replacement so went ahead without. It works, perfectly. Those third-party guys have really been taking the piss. I’ll post that video later today and link on here. Though I confess if I could get hold of those charge connector plugs l’d be making these and selling for say $250. I guess someone else will!
These aren’t quite the same - do you know if this is the company that made the connectors Pablo21?
Hi @Yako yes these are the ones. They are a custom service so you need to specify the precise design. The Mahle ones have this firm’s logo on them. A simpler route might be to replace the socket on the bike to a standard design. This would make life easier in terms of sensibly priced batteries and chargers, but would obviously void any warranty.
I thought about that, but if it’s for my bike, I can (and have) used the charger cable plug. But given more time (I’m always impatient) I would unscrew the charge port, lift it up to expose the cables, and splice into the two larger power leads and run the cable up inside the seat tube. Neater, and leaves the charge port available…
I wondered about the connector manufacturer in case anyone wanted me to make them an extender for half price. I’ll ask them what they’re minimum order quantity is, so thanks!
I wondered about the connector manufacturer in case anyone wanted me to make them an extender for half price. I’ll ask them what they’re minimum order quantity is, so thanks!
That’s brilliant thanks @Yako. If people choose to, they can buy the exact same battery sold for €500 in Europe and make their own dual battery system for about €150. It also means we can use any suitable charger should our original die. A Mahle original charger is a shocking €120. I would be interested to discover if the diode is already inside the bike, given it is designed for parallel batteries.
A repost of my post on the Cannondale forum:
Searching for extension cord for Mahle extender battery. We just got 2 Mahle ebikemotion powered Cannondale bikes. My wife is riding a Treadwell Neo Remixte. It was not designed to accommodate an extender battery. If mounted on the seat tube, the cord is a few inches too short to connect. I did purchase a
I have contacted both Mahle and Cannondale about an extension cord. Very unsatisfactory responses so far. Both directing me to the other and no one ready to take responsibility. It seems a bit incomprehensible that neither one of these companies will do the right thing and make a silly little cord which would add significant functionality (and help sell more bikes and $600 batteries).
I’d love to hear about alternatives or DIY options
Searching for extension cord for Mahle extender battery. We just got 2 Mahle ebikemotion powered Cannondale bikes. My wife is riding a Treadwell Neo Remixte. It was not designed to accommodate an extender battery. If mounted on the seat tube, the cord is a few inches too short to connect. I did purchase a
MAHLE Smartbike Systems Extension Wire for GCU.
However, it appears this cord is only for upgrading. In checking the cord, only 3 of the 4 pins on the connectors show continuity between the the connectors on each end. I am wondering about a diy attempt to operate on the connectors and connect the unconnected pins. Any suggestions for getting a functional extension cord greatly appreciated.I have contacted both Mahle and Cannondale about an extension cord. Very unsatisfactory responses so far. Both directing me to the other and no one ready to take responsibility. It seems a bit incomprehensible that neither one of these companies will do the right thing and make a silly little cord which would add significant functionality (and help sell more bikes and $600 batteries).
I’d love to hear about alternatives or DIY options
James Myres
Member
An update on the use of my homemade 3D printed extender:
I have had 2 of them working on my bike and my wife's bike for about 2 years with great results.
You can get into a situation where the bike is drained on a steep or long hill climb and the charging from the extender to the bike is slower. When this happens you'll notice the bike charging light on the bike starts blinking while you are riding until they are in sync again. I climb any where from 2,000 to 3,000 feet on rides from 25 to 70 miles and this has only happened a couple of times in the last 2 years. This means that the charging system on the bike already has some current limiting in the circuit that prevents a high current charging from the extender from pushing to much current in too fast. I've head that the Mahle X35 extender can experience the same thing on a long hill as well.
Another issue is that if the extender is fully charged and the bike is only partially charged and you plug it in the bike will go into the blinking purple error mode. To fix this you only need to charge up the bike separately and then the error will disappear when you plug it in and turn it on. Someone suggested a current limiter and this is probably a good idea, but I haven't had to change anything. I either charge them together when they are both plugged in or I charge the bike with the extender connected but turned off so only the charge goes to the bike.
I often take the extender off to save weight as I don't need it for rides under 50 miles. When I do this and need to plug the extender back in, I turn it on and if there no error light, I charge them together. If the error light comes on, I unplug the charger, I shut off the extender and bike, then I plug the charger back in the extender with the extender off so it can charge the bike only. After the bike is near full charge, I turn on the extender to let them balance together. If the extender has less charge than the bike, the current from the bike does not flow backward into the extender. I have seen no issues with this as if the bike is fully charged, all the current will flow from the charger to the extender until both are charged and balanced. This s probably because the max voltage from the charge is 42 volts and a fully charged battery is a tad over 42 volts and the lower battery absorbs the bulk of the current until they are balanced.
The reason I don't sell the extenders is because I don't have enough knowledge of he X35 system to put into the extender the safety circuitry necessary to be liable for a fool proof system.
I have had 2 of them working on my bike and my wife's bike for about 2 years with great results.
You can get into a situation where the bike is drained on a steep or long hill climb and the charging from the extender to the bike is slower. When this happens you'll notice the bike charging light on the bike starts blinking while you are riding until they are in sync again. I climb any where from 2,000 to 3,000 feet on rides from 25 to 70 miles and this has only happened a couple of times in the last 2 years. This means that the charging system on the bike already has some current limiting in the circuit that prevents a high current charging from the extender from pushing to much current in too fast. I've head that the Mahle X35 extender can experience the same thing on a long hill as well.
Another issue is that if the extender is fully charged and the bike is only partially charged and you plug it in the bike will go into the blinking purple error mode. To fix this you only need to charge up the bike separately and then the error will disappear when you plug it in and turn it on. Someone suggested a current limiter and this is probably a good idea, but I haven't had to change anything. I either charge them together when they are both plugged in or I charge the bike with the extender connected but turned off so only the charge goes to the bike.
I often take the extender off to save weight as I don't need it for rides under 50 miles. When I do this and need to plug the extender back in, I turn it on and if there no error light, I charge them together. If the error light comes on, I unplug the charger, I shut off the extender and bike, then I plug the charger back in the extender with the extender off so it can charge the bike only. After the bike is near full charge, I turn on the extender to let them balance together. If the extender has less charge than the bike, the current from the bike does not flow backward into the extender. I have seen no issues with this as if the bike is fully charged, all the current will flow from the charger to the extender until both are charged and balanced. This s probably because the max voltage from the charge is 42 volts and a fully charged battery is a tad over 42 volts and the lower battery absorbs the bulk of the current until they are balanced.
The reason I don't sell the extenders is because I don't have enough knowledge of he X35 system to put into the extender the safety circuitry necessary to be liable for a fool proof system.
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