Charging on tour: Alternatives needed
Posted by kapege@reddit | ebikes | View on Reddit | 54 comments
Up to now I charge my second battery with solar and swap them. Within the trailer is a step-up MPPT controller to 42 volt and charging is ok on a sunny day. But the Bosch battery system is proprietary. And officially you can only charge with a grid power brick.
So shall I upgrade to a power station? The Jackery Explorer 500 V2 looks reasonable and would act like a 3rd battery and range extender. Or should I use an existing 12 volt MPPT controller together with an existing Li-ion battery with \~500 Wh and just buy a simple 500 watt inverter for the power brick?
Or do you have another idea? Charging at a stationary charger is no option, because I don't want to wait on a parking lot for three hours, but charging on the ride. And I can't always charge at a campsite in the evening, too.
Habu93@reddit
Wow! Sounds like freedom being on the road! You inspire me to do the same!
whot3v3r@reddit
A power station is too expensive, heavy, and you have too much conversion loss. Get rid of your closed Bosch system and plug a MPPT directly to the battery.
I have a recumbent trike with a 200w panel on top.
Cargobiker530@reddit
It took way too long to get to the right answer. The problem is the Bosch motor system which will only work with chipped Bosch batteries & chargers. It's not a system that's friendly to DIY electronics. A Bafang motor, KT controller, UPP batteries and 12 to 54 volt boost converter would hold a lot more power, be easier to repair, & cost a hell of a lot less.
That's not going to help OP much unless they're interested in replacing the bike because non-Bafang mid-drives usually have proprietary motor mount plates. I have deep safety concerns about touring on a folding bike anyways so my approach would be to start with a steel framed, 26", analog mountain or touring bike & work from there.
whot3v3r@reddit
In fact I'm a bit confused, OP seems to be able to charge his battery, so why is he talking about adding a power station with an AC charger ? Sure he does not charge the battery that is plugged to his bike but is it really a problem ?
There is a very easy trick to charge I found in 30 seconds: provide 5V to one of the battery pin https://www.youtube.com/watch?v=vIu4cTpSew0
u/kapege do you use that trick ? what do you want to change and why ?
That bike looks well built and costs about 3000€, he shouldn't have problems with the folding and it can be an advantage if he want to take trains with it.
kapege@reddit (OP)
That's what I'm charging with at the moment. That's my 5 volt auxiliary power system:
The problem with that solution is, that the battery charges with max. 70 watt only instead of 250 watt with a wall brick. With all the shades on the move you can't charge one battery completely during a day long trip. With a power station as a buffer I could charge the 2nd battery way faster.
whot3v3r@reddit
What makes the power is the solar panel, it looks like around 100W so 70W is a realistic power under unideal condiditions.
Your power station will also charge at 70W so you will have the same issue when it will be empty, and overall it will be worse since you have more power conversion losses and more weight to transport.
You have 2 solutions: more solar panels including foldable ones that you deploy when resting (someone posted a picture) and use less power.
Not sure if it will work well but you can try to put 2 panels in a V shape on your trailer
Cargobiker530@reddit
That makes a lot more sense than even considering a Jackery power block. Pretty good internet sleuthing there.
SolarTrails@reddit
Solar charging is what I chose. I currently use two 100 W panels and have a nearly 1 kWh battery. It’s slow and only works on sunny days, but the sense of independence is priceless. I plan my routes with the weather forecast in mind, yet I still sometimes end up in situations where solar charging isn’t possible. In those cases, I stop at a pub or restaurant for a few hours. Have a look at my YouTube channel (@SolarTrails), it focuses on the practical challenges of solar-powered bike trips.
Tobinator97@reddit
I have the same trailer but converted it to have a proper suspension with 250mm of travel so I can shoot down trails without an issue. I can only recommend that
SolarTrails@reddit
Sounds great. Do you have photos of it?
Tobinator97@reddit
It's in the garage right now. I have to redo the bearing for the swing arms as they are worn out after a few thousand miles. Maybe I post some pics when reassembled
leahfirestar@reddit
Thank you I would love to see photos !
leahfirestar@reddit
How did you do that ? I have the same trailer although I'm disabled now and can't cycle I have a power wheelchair and I hook the trailer to that when taking stuff to the recycling centre twice a year. My dad decorated it for Christmas last year for a group Santa cycle ride .
Tobinator97@reddit
First of all it requires lots of welding and turning parts. But basically you attach two solid turning points to the frame where two swing arms are going to be attached. Then you have to manufacture the swing arms and a mount for the two shocks. When done it's drivable but in hindsight plan for a sway bar because the trailer will lean into curves quite heavily although I haven't thrown it over yet. Go with air shocks so you can adjust the ride height properly. With this setup I was able to deliver beer blasting down bad forest roads at 30+ mph without foaming over immediately after the ride so it's quite smooth and satisfactory to watch the suspension working
RoundSyrup4424@reddit
You are living the dream! #jealous
FOX_ITA@reddit
That looks like a great setup! Would you mind to share the what your purchased/built as solar panel or anything that allows to charge a battery? I was looking into it, but I have zero knowledge. Thanks 🙏
SolarTrails@reddit
Thanks. My setup is never final, it’s an ongoing process. I often tinker with new panels, charge controllers, etc. You can find my equipment here:
https://docs.google.com/document/d/1oVASDqiw27yUMoG-jX3dFSS8m96FC5Jnb2V5Zfdev7o/edit?tab=t.0
I’ve also made a video focusing on the solar charging aspect (I plan to update it, as a few things have changed since then):
https://youtu.be/q54b3_SaQFo
If you have any questions, feel free to ask. I’m not an expert, but I do have hands-on experience with solar-powered bikepacking trips.
Healthy-Process874@reddit
Do you try to get up before dawn and ride to mid day?
It seems like a good strategy.
I've noticed that my batteries take about 5 hours to charge, and that would allow me enough sun to get that done.
SolarTrails@reddit
Exactly. I usually wake at first light, make coffee, pack up, and get moving. If the night is especially wet and my tent is covered in dew, I might wait for the sun to dry my gear.
Yes, charging the battery can take forever. In my case, that’s a feature, not a bug: I’m extremely lazy. Ideally, around midday, I’d look for a good meadow or clearing, set up the panels, and then have hours after hours to prepare lunch, read, listen to podcasts, watch a movie, walk around, or take extremely important photos of bugs, flowers, clouds, rocks, and leaves. :-)
FruitPuzzleheaded310@reddit
how effective is that?
kapege@reddit (OP)
I can ride with solar-only on a sunny day, but else I'm doomed until I'll find a campsite or another solution to charge in the evening. I don't want to waste 3-4 hours per day on a ugly charging station.
FruitPuzzleheaded310@reddit
how much cost is that full system with bike
kapege@reddit (OP)
Look-up yourself for Tern Vectron S10, Burley Coho, 2nd Bosch battery 500 Wh and do the maths.
100 watt flexibe solarpanel: \~50 €. MPPT step-up charger: 28 €
_KeepOnTrucking_@reddit
Honda EU1000i for cloudy days...
kapege@reddit (OP)
I already thought about that. A German guy built a camping quadcycle with a bicycle trailer and a Honda within a box for insulation. https://www.youtube.com/watch?v=xUuk6--0AgA
wojtek30@reddit
Surely at that point just invest in a low CC motorbike
footsnax@reddit
I use a Bluetti power bank to recharge my second battery on the road, but that's just effectively six more batteries and the weight and maintenance are a constant hassle. The bank can charge with solar but usually I've found power to recharge it before I need to sleep.
Has anyone figured out a way to recharge with backpedaling? I have a flashlight and radio that can crank charge, it seems like that would be an obvious engineering problem to tackle.
kapege@reddit (OP)
Backpedaling? Do you mean recuperation? That does not work for my or any middle motors and it does not extend your range much and it has extra weight for the more complex controller.
Healthy-Process874@reddit
Honestly, it might be interesting to have a kickstand that gets the rear wheel off the ground and a reversible mid drive to generate electricity with Gilligan's Island style.
You'd essentially be negating the advantage of the electric assistance. Which seems silly, though.
I mean, you are generating the wattage to produce the electricity in the same way you generate it to power the bike.
Cranking it enough to power a tablet to watch movies on might be pretty easy, though.
That would only be 10 watts or so. You could trickle charge a battery that way if you stayed in one place for a while.
footsnax@reddit
I'd buy a Gilligan's bike.
Honestly it seems so duh, I know some bikes have brake regeneration already. I can crank my NWS radio for ten seconds and it'll run for six hours, it just seems like an easy way to turn Gatorade into battery power.
I'm not asking for infinite range, I just think it'd be nice to gain a few miles by backpedaling when I'm going downhill. I can get an easy 40 miles with my current rig and cadence, I'm nearly doubling that with inconvenience by carrying two batteries, if I can get 50 then I can go see my mom and come home without charging while I'm there and worrying about it the entire last third home.
This really seems like something an engineer would have thought of and couldn't sell, tried it and failed, or it's absolutely genius and I someone's gonna be a millionaire because I just blasted it online.
Healthy-Process874@reddit
Some people have fooled around with AWD bikes.
I think Seth from the Berm Peak channel put a front hub motor on a bike with a mid drive.
It would add a lot of weight, but if you had a direct drive motor you could have regenerative braking downhill.
I actually talked to an AI about this.
It suggested a throttle to vary the resistance on the downhill. So that you can modulate the braking.
I don't know if it was hallucinating or not, but it sounded cool.
I'm heavy and often dragging a trailer, so steep downhills can be scary. Regenerative braking would certainly improve my stopping power.
footsnax@reddit
This sounds like a... yes in theory but no in practice, so a very AI thing to say lol, so my money's on hallucination.
If there was a way to apply resistance to force and generate more energy from the applied force then the energy crisis would be solved. The world would be that Black Mirror episode where everyone's just constantly on Peletons and singing that one song.
I just wanted to recover some energy while both my body and the battery was out of use. I'm not doing anything on downhills, neither is the bike, why can't I just crank it to buy a hundred more yards when I'm coming out of the hill, right?
Healthy-Process874@reddit
The resistance of the motor for the regenerative braking.
I probably didn't relate that very well.
_haha_oh_wow_@reddit
FYI - Using a battery to charge a battery is inefficient (on the other hand, it's better than not having a charged battery I guess).
footsnax@reddit
Oh I'm fully aware. I'm losing my mind trying to find a perfect solution, I'm using what I have in the meantime. I'd do a hundred miles a day if I could, and this gets me the results I want but it's stupid and just sucks along the way.
_haha_oh_wow_@reddit
Any reason you don't just get extra bike batteries instead and just charge them directly?
footsnax@reddit
I have two and I already had the bank, any more is just more money for a net equal on range. I roll with low PAS, no throttle, and the Bluetti is basically a wall outlet so my backup is usually mostly charged before I need it.
Aside from the weight and hassle of swapping, it's only really inconvenient when I get stuck in a loop where neither of them gets a full charge before I need to swap. Both at 80% means both are at 70% next charge, means both are dead next charge. If both are dead it's like pushing a boat uphill from all the weight.
Less battery means less weight, but also less range, but then easier to pedal without assist, but then I'm just riding a bike with extra weight so why have a battery. I'm stuck in the constant fight to find the perfect middle ground, I want maximum range that is also still just a bike.
robotcoke@reddit
What bike is that and how far are you riding? That looks like a pretty cool setup!
kapege@reddit (OP)
It's a Tern Vectron S10 and a Burley Coho trailer. I like to ride \~ 100 km per day.
ellipticorbit@reddit
Looks like a Tern Vektron
DonnPT@reddit
I'm relatively clueless here, but ... you have a second battery that works in your system, and a Bosch battery that doesn't? Both batteries have AC house current chargers, I assume.
Here's where I fully display my ignorance - what if you bought a third and maybe fourth battery like the 2nd one, and left the Bosch battery at home? Then you'd be hauling 1 AC charger, your solar setup, and as much battery as you think you need.
kapege@reddit (OP)
I've two Bosch batteries only. With the existing setup the batteries will charge with 70 watt instead of 250 watt. That's due to the non-encoded charging mode. The full-power mode is only for the closed Bosch setup with the Bosch wall brick.
RoundSyrup4424@reddit
A solar panel on my bike sounds like a dream! But the wind gusts around here on my panniers are enough to nearly knock me to the ground, and solar panels are larger, and I don't have room anyways, so a dream it will remain. Following this post though because I love this so much!
Healthy-Process874@reddit
Assuming that you're riding mostly on pavement a flatbed trailer is low to the ground and only weighs about 15 lbs. It's extra rolling resistance, which is a negative.
The single track trailers have lower rolling resistance, but are a different set of problems.
Weight needs to be loaded in them very carefully, and they require effort to keep upright at stops.
I noticed that the wind affects them quite a bit, too.
They do roll over gravel and such better, though.
snoogins355@reddit
Camp ground that has power hook ups
Healthy-Process874@reddit
Campgrounds with electric can be $50 a night and maybe more in the US. Might as well get a cheap hotel with AC and a shower.
snoogins355@reddit
Couch surf and ask to plug in too. If people are offering a couch, they'll probably be cool with a few kwh
BenTheHokie@reddit
This is the kinda project I'd work on if I were unemployed. Can you poke around on the charger cable and figure out what voltage and current it's providing, size a solar panel appropriately with overhead and drop in a buck converter? Perhaps MPPT is out of the scope of the project. I'd avoid going DC -> AC -> DC. I think that's just going to lead to a very low efficiency.
ChemicalConclusion71@reddit
Perpetuum mobile
Middle_Pineapple_898@reddit
You lose a lot of efficiency when converting between AC and DC so I would seek ways to avoid that. Maybe someone can rebuild the charger brick to run on DC?
saihtame@reddit
He could just use a converter to pretty efficiently ramp up the voltage from the solar to match the ebike.
BoringBob84@reddit
Floating any battery on the bus like that will seriously degrade its life, but doing it with a Li-Ion battery could put it into thermal runaway.
Battery chargers have intelligent circuitry that controls the voltage and the current according to the battery's state of charge.
jameath@reddit
Buying a jackery or an inverter will both come with more or less the same benefits and inefficiencies, how are you charging the spare battery now? Just 42V straight into the battery?
The use the proper charging brick, you need mains, but turning solar DC power into AC will always waste a little energy in the conversion.
I’d say work back from using the trailer to lug about a huge battery, 24 / 48V - 100+Ah, (remember higher voltage means you can use thinner wires to connect everything together) an then set yourself up to be able to charge that battery as many ways as possible, a half decent inverter might have a mains to battery charging path, so then you can plug it into the mains whenever you can, soak some power up from the grid, and then get as much solar as you can physically tow, maybe have some panels that are not in use when cycling but can be quickly and easily laid out. Make sure your solar charger can handle the maximum possible output of the panels,
Super cool setup, I’d love to do a solar powered e-bike-packing adventure.
circumcisingaban@reddit
bro is a Far Cry/GTA side mission