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[flei]

Thru email exchange with Luna support I think we figured out that the problem was that the foam tape (added to stop rattling) was not allowing the battery to seat fully without a lot of force being applied. As that foam compressed further with multiple insertions the situation improved. So actually a pretty small problem that fixed itself!

[paxtana]

Glad to hear it!

[flei]

Sorry paxtana , I can't figure out how to reply to your comment above. Thank you for responding.

I did open a trouble ticket and have now gotten a response. I'm considering this issue solved for now. Since I lubed it, I've cycled the battery into and out of the frame numerous times and it is getting easier to get it to lock into place. Maybe with wear, tear, and vibration of riding it will continue to get easier over time? I'll consider the problem solved for now but will follow up if it worsens again.

[paxtana]

Can you upload a video of this to streamable.com or youtube (you can restrict it to only those with link can see it) and link to it so we can have a look? What order# was this? Have you created a trouble ticket? https://lunacycle.com/support-request/

[flei]

Received a new Luna X2 yesterday and though the battery came out as it is supposed to, when I re-insert it I cannot get it to lock into place. It appears the bolt on the lock does not align with the receiver on the battery case. I cannot see any obvious interference etc. in the compartment and the battery seems to seat properly. Anyone seen this issue and/or know a fix? Thanks.

Well I was able to get the battery to lock in. I put silicone grease on the area where the top of the battery slides against the mount and on the lock bolt and can now slam the battery into place. But it isn't pretty. Wondering if it is supposed to really require so much force to seat? Is there some adjustment I might make to make it easier?

[flei]

Received a new Luna X2 yesterday and though the battery came out as it is supposed to, when I re-insert it I cannot get it to lock into place. It appears the bolt on the lock does not align with the receiver on the battery case. I cannot see any obvious interference etc. in the compartment and the battery seems to seat properly. Anyone seen this issue and/or know a fix? Thanks.

[Retrorockit]

The "size" of a battery is expressed as Watt/hours,W/h. Basically you add up the Watt hours of all the cells in the battery and that is the "size" of the battery. The cells can be wired up in several different Voltages. usually multiples of 4V since that represents a charged 3.7V. cell.
At lower Voltages you need more Amps to produce the same power. This requires bigger wires. I asked a bus engineer why they used 24V. in bus electrical systems when cars and trucks used 12V. He said it saves 300# of copper wire per bus. You get more power at the same amps with higher Voltage, and no loss in W/h as long as the battery has enough cells.So it's more versatile as long as the components can handle the Voltage, and cooling for the extra power is there. 48-52V is preferred because it can run on standard 60V electrical components. 56V and up requires more expensive parts. 36V came out of lead acid batteries where 12V. multiple is common. Going form 36 to 48V. there adds size and weight with lead acid batteries. The built up cell type batteries don't have that issue. But a lot of controllers came from the lead acid era so 12V multiples are easier to build. So 48V is standard now. It may be hard to find a display with native support for 52V. etc. But 52V is fairly common.

[stts]

Well, your just looking at the wrong thing here. There is no question that Ohms laws says that it's easy to build the same size battery at 36v as is 52v. The problem you see comes up when you hit the throttle hard or from the standing start when max current is demanded. That sag in voltage happens because of battery resistance. So when you sag down to 25v, the controller will be demanding 38amps to launch the bike as commanded. But the mosfets will not be sized to carry that much current. So safety circuits kick in to current limit, or controllers simply blow up. Either way, you don't get the power that you commanded. If you do have a better 36v controller that will supply that current, then the power has to go thru the battery wires and the controller wires that are not big enough to handle this current effortlessly. So wire resistance causes even more resistance to the transmission of the power to the motor. Additionally, the windings in the motor use wire that is of smaller gauge to cut the costs of building the motors. And that's even more resistance that interferes with power delivery to get hard acceleration. So the problem is not the voltage as much as it's the push to make cheaper components and build quality. Companies are not interested in putting larger gauge windings in motors when they can crank up the voltage instead. The battery does not get bigger or smaller, it is simply rearranged. You still get the same miles traveled because it's still a 1Kwatt battery. But they can sell you cheaper made motors and wiring and controllers. In Europe, all power in the walls is 220v. That means all the wiring in the walls is half the size and expense that it is in America. All the gizmos use smaller size motors and controllers that still deliver the same size power. All the breaker boxes are smaller and cheaper, as is all the connector materials in the entire system. But it still does the same work for them as our power does for us. They could switch to 440v power if they choose, but its just too dangerous when they get their finger on it. Oh, another big reason for 110v in American is that our houses are made of wood that burns down in electrical fires. European homes are mostly made of stone. They don't catch fire when their 220v arcs and sparks.

So you see, 36v is just more expensive to setup the way people want it than 52v. And eventually, the voltage will be 97v to make motors and controllers even cheaper and more profitable to make. And batteries will get physically smaller when they make the next improvement in the actual battery chemistry. So until then, batteries will be about the same size no matter what voltage you pick. A 97v battery will not be any smaller with the current cells we have. But no bigger either.

[Cezar]

I don't quite understand how a 36V battery can be the size of a 52V battery. Maybe I don't understand something.
I build an e-bike, import engines and buy batteries made "according to the art" from cells of well-known manufacturers - eg LG MJ1 or Sanyo - most of them with a voltage of 3.7V and a capacity of 3500 mAh. I put the battery housings on the slanted tube of the frame in the "place" of the water bottle, although much larger - we use screws and add two more - fixing rivet nuts. The housings are the same for 48V and 52V, 36 I have never installed. A 48V battery has 65 cells and a 52V battery has 70 cells. Just because they fit in the same case doesn't mean they're the same size. A 36V battery is 10x5 = 50 cells. For large batteries 21Ah 36V with 6 sets in parallel we have 60 cells.
Motors allowed in Europe have a maximum of 250W, I install up to 1.5 kW. It is known that for a voltage of 36V, the maximum amperage is about 7-10A, for me it is 28-30A. for 48V - up to 52V. So we try to compare incomparable things.

[stts]

In practice, I can build you any battery at any voltage you want in multiples of 3.6 volts. And they would fit in the same case. Because they all use the same batteries. So a 1kwattH 36v battery is the same size and weight as a 1KwattH 52v battery. They both hold 1KwattH of energy and do 1KwattH of work. And fit in the same amount of space. But the wires for a 36v system have to be lots bigger, and the Mosfets also have to be much bigger because the current is much higher in a 36V system than in a 52v system. Thats the only difference. 52v is being used so that cheaply made motors and controllers will not fail in use. Those same motors and controllers would over heat if they were run by a 36v battery. Its all about money and profit is why voltage is going higher.

As you said, power is V xA. so 1000watts = 36v x 27.7A = 52v x 19.2A. So you see, there are less amps at the higher volts. The problem gets worse as the battery runs lower. When the 36v drops down to 26v as you posted, then 1000watts = 26v x 38.4A. That is a huge increase in current that companies cant afford to wire a bike for or install mosfets to handle. So the wiring they do use heats up and the mosfets burn out. And the motor wiring would also heat up considerably. To stop this they increase battery voltage. Then they can use smaller wiring, smaller mosfets and motors with thinner windings with less copper. Because the current in a 52v system is much less. Its a money game. If you spent the proper amount of money you can build a 36v eBike with the same power that will do the same as the 52v eBike. It will just cost you more. One day we will have ebikes over 100volts. Doing the same work as a 52v bike now. But even cheaper to build. With battery packs the same size as now. Pack size will not drop till we get a battery that holds more power in the same cell.

[Cezar]

I don't want to be smart here - but the power is V x A and for a 36 V battery to be more powerful than a 52 V battery, it must be mobno expandable in parallel. .- there is no housing that would give any advantage to a 36V battery over a 52V battery. . A regular 52v battery consisting of 14sp5 gives - 52 x 5 x 3.5 = 910H and a large 36V battery is a 10s4p which is 36 x 3 x 3.5 = 510WH which is considered huge but is actually slightly more than half the value of the battery 52V considered classic. So in practice there is no such thing as a 36V battery that would defeat a 52V battery - that's obvious..

[Cezar]

It depends on how many cells you connect in series and how many in parallel - it's obvious. - the amount of Wh tells about it - that is, how to build a battery - the classic is 48 V, i.e. 13s4p, i.e. 13 cells in series and 4 sets in parallel.. for a 52 V cell, it is 14s5p - we have to fit it all in a package on an oblique frame.. More it does not fit - but there is such a casing, quite high 14.5 cm and it holds a set of 21 Ah, i.e. 14 x 6 = 86 cells (3500 mAh and 3.7 V)
3500 x 6 = 21Ah and 14 x 3.7 = 52V ...

[stts]

Nope. The laws of physics disagrees with you. Its not about voltage. Anybody can build a 36v battery way bigger than a 52v battery if they choose to. And then the 36v battery will allow the 36v motor to outperform the 52v motor. There are plenty of 36v fork lifts in use that can on a single charge outperform a dozen fully charged 52v eBikes on any given day. The sole reason people are choosing to use higher battery voltages is that it significantly reduces the costs of the copper and semi conductor materials. That's it. So those that cut corners and make cheap 36v eBikes with thin cheap wires will see problems developing power as the 36v battery gets lower on charge. If the 36v eBike was not built by using substandard materials, It would perform identically to a comparably powered 52v eBike. No question about it. Absolutely no question about it. Ohms law says so.

[Cezar]

The bicycle engine runs on voltage drop - you have 10V to 14V available depending on the battery. For a battery with a nominal voltage of 36V, i.e. 10V, for a 52V battery you have 14V available. Counting from full charge to cutting off the battery by BMS.. Hence, the engine power decreases during battery discharge and for a battery with a nominal voltage of 52 V - the charger charges up to 58.8 V x 28A = 1650 W and for a battery close to discharge, i.e. for 45V we have a power of 45 x 28 = 1260W. That is a decrease in power during the discharge process by 400W. Of course, for batteries with a voltage of 36 V and below, it looks quite dramatic and strongly felt. With a 52V battery, it is imperceptible.

[paxtana]

Not sure, seems like operations has opted for not making them available separately. But if you have bought a kit from us please email support@lunacycle.com with the order# and we can sell wolf for you via special order ;)