E-bike battery charging while riding

[dogman dan]

Personally, I never saw more than 3% regen. But it depends on where you ride. If you stop every block, then regen will be more and more worth having. But if your stops are only once every few miles, then you can coast it out more efficienty.

Also worth noting, the smaller the pack, the higher the same wh of regen will look when expressed as a %. I just found that even on a long ride, I really didn't get enough regen in wh, to take me far enough to care about. Less brake wear is the real benefit for the most part. The downside is you do need a superb torque arm to run regen, preferably a clamping type.

 

[agniusm]

I bet there are people with good numbers, no doubt, but talking about the majority, it depends from the point of view. My guess is based on the distance traveled cause this is most important parameter. Stopping and going frequently is not most efficient way, you use up more energy in the end but get higher recuperation. You travel without stopping as much, efficiency goes up but regeneration of energy is lesser and in the end based on distance traveled in both cases i don't think it is considerably if any more than >5%. Just my 2ct.

 

[llile]

I think 5-10% regen figure is for cars. Bikes must be more pessimistic.

I ride on country roads, not too many hills, and i get 1% or 2% regen at best. I lean on the e-brake every chance I get, but if you are not in stop-and-go or hills, you'll not see much benefit of regen. It was a free benefit of the setup I had, so I left it in place.

 

[llile]

I think we are missing the question of the original post. Let's say you had a hypothetical black box that could deliver power to your bike - would it be ok to use said black box hooked to the charging input? And what chemistry are we talking about?

My own situation - I have a "72 V" LiFePO battery that usually runs about 83V when fully charged. Am I to assume this hypothetical black box should work to give me a few extra miles? So far answers on this post indicate that it would be OK to do this????

I have a long commute, and am always begging for opportunity charges where I can find them. Round trip 40 miles (yep, I E-Bike this regularly!) I have a 40 AH battery, and need it all for miles and also just for current capability. I'm discharging at about 0.6C. If I had another 10 amp-hours cushion for range I'd feel more comfortable.


What if this "black box" was a 10 AH battery with a boost regulator (my design) that would produce 84V DC or so? plug it in to the charge port when I get to my destination, then stop it with the range anxiety already. It could be a stock 36V 10AH Ping (got one in the garage!) if there was a converter to go to 84V.

The boost regulator would have to cut out at the 10AH battery's minimum voltage, and regulate at a proper charge votlage for the main pack. An interesting design challenge, however doable. Is this what the O.P. is driving at?

 

[dogman dan]

The two methods that seem to work best both charge the battery through the charge port of a battery with bms, or a naked batteries mains.
The source can be a charger plugged into a gas generator, or it could be a solar charge controller plugged into solar panels.

You do have to limit amps to what the bms can handle, or the charging current limit of a naked battery. Can't plug a full battery into an empty one, without ruining both, or at least causing some serious wear on them.

 

[UKTab]

Hi llile
Yes my question (somehow mis-interpreted initially) was can you charge batteries at the same time as you're using them. If so, what equipment would be needed?
Thanks!

 

[Jon NCal]

Give details about your charging power source. Otherwise we just have to guess about the details and problems/solutions.

 

[UKTab]

Give details about your charging power source. Otherwise we just have to guess about the details and problems/solutions.

Hi Jon, Without giving too much away, one option I'm looking at is solar. The other is a wind system I'm developing. I'm looking for a way to 'plug' these into a device which transmits their power into a battery charger, so I'd need something that could accept multiple sources.

As I mentioned earlier, I'm just an ideas person. I have no technical background, which is why I'm in need of help!

 

[Jon NCal]

Okay, do a search on solar charge controller.

 

[dustNbone]

I'm looking at doing something like this if possible. The charging source will be a 1000W Honda generator in a trailer, for some long touring/camping that I'm planning to do. Plugging into mains at the end of each days riding simply won't be feasible where I'm planning to go. There's just no such infrastructure in some places, so either I need to charge at camp (rather not listen to it, even though it's a very quiet generator), or charge on the road.

My battery is a 16S1P of A123 AMP20 cells, and BMS is rated for 60A charge and discharge. Motor is a BBS02. I'd like to use an 800W charger to give the generator a solid load. Recommendations for chargers would be very welcome, I'm pretty new to this.

So what I'm wondering is basically what I understood OP to be wondering as well, can I just connect the charger to the charging port of the BMS and be on my way? 800W at 60V is under 14amps, so by the numbers it seems it would be fine but I may well be overlooking something.

 

[UKTab]

@Jon NCal I found a 12/24 V solar controller, thank you, but my question was can I charge the battery while the battery is in use.

 

[amberwolf]

but my question was can I charge the battery while the battery is in use.

You can easily do so if it has a separate charge port from it's discharge port, by connecting your charger to the charge port just like you would if it was not in use. If the charger outputs more current than the controller pulls from the battery, then it will charge the battery up. If it does not, it will simply slow down the rate at which the battery is discharged.



If it does not, then you can parallel your charger with the discharge port. Then as long as the charger outputs more current than the controller pulls from the battery, you will be charging the battery. Otherwise, you will simply be lowering the amount of current the battery is outputting, by the amount the charger supplies at the then-present system voltage. (same as when using the discharge port).

Without giving too much away,

If you don't tell us what you're doing and how you're doing it, we can't really help you with those technical details you say you need help with.

Why is it so secret? :? This forum is about sharing information and ideas, and that's what we're trying to do with you--share our information with you. If you won't share yours with us, why should we share ours with you?

If you're developing a product for sale, then coming here to an open-source forum to get info without also sharing info is bad form, and rude.

If you're making something for yourself, why not help us help you?

The reason you are getting a lot of speculation and apparently unhelpful info and answers is because you won't tell us enough to let us give you the answers you need, so we have to guess, and everyone's guess about what you're doing will be different, so you will get different answers, most of which won't be helpful, and just wastes your time and ours.

The other is a wind system I'm developing.

As long as the wind system is used only when you are stopped, then it can help provide power to charge. If you use it while riding, you are just taking power from your forward motion, which can never charge your system, only discharge it, because you then have to use more power than you got back to recreate that forward motion and keep your speed in order to keep the wind up to keep charging, etc. If you use it to help you stop, like regen braking does, then you can recapture some of the energy that would otherwise be lost as braking heat, but if you use it while you want to keep moving, you're just wasting more power than you can get out of it.

As I mentioned earlier, I'm just an ideas person. I have no technical background, which is why I'm in need of help!

And if you really want help, you have to tell us as much detail as possible!

 

[999zip999]

If you are wanting increase range instead of a experiment in charging a battery. You should just pedal start to 4 miles an hour than light on the throttle look ahead get your hand off the throttle and Coast to the red light or pedal when you can help assist with pedaling keep yourself to 18 miles an hour and you will go very far. Yes regen is good for 6 to 10% maybe less. I see 50 amp spikes on region thru my CA. Muxus 3,000 and A123, yes I know this is just a spike. But you need a super battery or a bms to control it and program your controller regen and regen voltage to match battery.

 

[UKTab]

Thanks amberwolf. Sorry about being cautious but I've had ideas ripped off before and other people made money from them. I'm in no way saying anyone here would do that but you never know who's searching for other peoples' ideas.

Ideally I'd like to find someone who knows about the techy side, like you, and get my ideas made into physical products. Every search I did for help led me here

 

[999zip999]

AW I know what he's up to, a D.D. motor set in regen with a big propeller attached and mounted on the Handlebars for a wind turbine. Always working when going forward.

 

[UKTab]

AW I know what he's up to, a D.D. motor set in regen with a big propeller attached and mounted on the Handlebars for a wind turbine. Always working when going forward.

Don't forget the wings for lift (would equal less friction)

 

[999zip999]

Chitty Chitty Bang Bang. Wing foil for Lift.

 

[dogman dan]

If it's a generator, simply plug the charger into the battery. Nothing much new to sell there really. 800w chargers are out there, BMS battery one affordable source for higher watt chargers. The setup won't overcharge your battery, and if you are riding a reasonable speed, it won't result in discharging the battery very fast. 800w is enough to take a fairly heavy bike or trike 20-25 mph.

If solar, or wind once you are parked, equally simple, but in this case you need a charge controller rather than a regular AC input charger.

I'd say experiment with the generator first, since you already have a charger for it. A 250w charger you already have is enough load for a small generator anyway, if yours pulses when on no load.

I've done quite a few road trips, where I take bikes and the generator, and camp in the car. A small generator to charge works good, I can even charge as I drive to the next spot if I'm towing a trailer to carry the bike.

 

[Lurkin]

I'll bite. This threads a bit of a joke really. You want to know how to power a bike with solar, yet act coy about the details, yet admit you are learning from the forum anyway :? This isn't new, unless you have invented a new hypercodumodulator which somehow makes it different to what others are doing already. In which case, you have already admitted you don't have the technical knowledge to make it anyway....

Unless you can find a turbine which somehow will be more aerodynamic than your body shape, will propel you at the same time as operating a generator - its a fail. It literally relies on the friction of the wind you are propelling into to turn the rotor and charge your battery. Meanwhile, no doubt you are using the same battery to propel yourself forward... with losses between the two as well....

 

[dustNbone]

I think the OP was really just interested in the ability to charge at the same time as riding, same as me. I'm just interested in occasionally pumping 800W or so of Honda power into the system to extend my range going over the mountains. I have no illusions of using anything other than bad old gasoline to do so on the move. I think my questions have been answered, seems like it's a go. Generator weighs under 30lbs without fuel, fits nicely into the single wheel BOB trailer. My only remaining step is to find the right charger for the job.

I just can't see how attempting to capture the energy of the wind passing (then converting it to electricity and back to mechanical energy) is going to be more efficient than finding a way to cut through it, but as far as I can see that's not really what OP was asking. That part is a secret.

 

[UKTab]

Lurkin, the fan / turbine comment was a joke, yes, and so was the wing idea, but thanks for your advice.

If you know how I can mark this as 'closed' or 'solved' that would be more helpful

I'll tell all if I get this thing running, so no more secrets then

 

[LockH]

Hi. Regen under way? Option is to reduce energy consumption per mile while underway... etc. One easy way is to streamline the bike/trike a la "velomobile"... But if ya paper that shell outside with "thin film" solar cells... One fav thought I'm thinking about is another "solar", as a sail to use any wind (energy) as an assist to my assist. See "spanker" sail. One problem in all of this maybe is adding any more mass ("weight") to the vehicle that uses more energy to accelerate or go against gravity ("up hills"). Urban rider? With plenty of coffee shops, restaurants, etc along various routes and at work I carry an small, pocket-sized charger where stopping anywhere and plugging in means zero time spent actually watching the battery recharge.

G'Luck. Charge early and charge often. Hehe
L

 

[UKTab]

Hi. Regen under way? Option is to reduce energy consumption per mile while underway... etc. One easy way is to streamline the bike/trike a la "velomobile"... But if ya paper that shell outside with "thin film" solar cells... One fav thought I'm thinking about is another "solar", as a sail to use any wind (energy) as an assist to my assist. See "spanker" sail. One problem in all of this maybe is adding any more mass ("weight") to the vehicle that uses more energy to accelerate or go against gravity ("up hills"). Urban rider? With plenty of coffee shops, restaurants, etc along various routes and at work I carry an small, pocket-sized charger where stopping anywhere and plugging in means zero time spent actually watching the battery recharge.

G'Luck. Charge early and charge often. Hehe
L

You're from Canadia... so heat is not a problem Just kidding Lock

 

[Lurkin]

You ask a mod to lock it for you. Not usually done unless there's something inflammatory going on. Other than that, it will just await your return when you have got your product working.

 

[motomech]

The OP is a spammer.