60v battery charging/discharging specs

wntrhwk68

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Hello, I have an Ebike with a 60v/20amp battery and I am curious if anyone has any details, or know how to get the details, of this battery. Specifically I would like to know the charge/discharge voltages as read from the battery terminals. I have had trouble with the C and P settings and the vendor has been zero help with this so I don't trust the display until I get some real voltage numbers to match up with what the display is reading. I have built battery packs before (LIFEP04) and know the value of not overcharging every time you charge and not discharging to far. Thx for the help.
 
If it is standard Li-NMC (18650's or 21700's with charge ranges of 3.0v-4.2v) these charts will be accurate for the charge levels.


You mention C and P settings... is this a KT hub motor controller?
 
What is the battery chemistry?
Li-Ion. So the display shows 2 bars out of 5 and 62.8v, I am assuming these numbers are incorrect, I just don't know because the C and P settings are probable wrong, also only 20 miles on fresh chg. There is a little battery status button on the side of the battery, it shows 4 green lights out of 4.
 
If it is standard Li-NMC (18650's or 21700's with charge ranges of 3.0v-4.2v) these charts will be accurate for the charge levels.


You mention C and P settings... is this a KT hub motor controller?
KT controller, KT 8HU display, Hentach motor
 
If it is standard Li-NMC (18650's or 21700's with charge ranges of 3.0v-4.2v) these charts will be accurate for the charge levels.


You mention C and P settings... is this a KT hub motor controller?
As shown the voltage is nearly 63v, but the graph next to the voltage shows only 2 bars left. When I go for a ride the bars drop even more.
 

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If it is standard Li-NMC (18650's or 21700's with charge ranges of 3.0v-4.2v) these charts will be accurate for the charge levels.


You mention C and P settings... is this a KT hub motor controller?
Sorry, replied to the wrong person, KT controller, KT LCD8HU display, Hentach motor
 
Personally i've never trusted the battery bar read-outs on my displays and / or battery. I prefer going with the voltage read-out and keeping an understanding in my head about percentages of charge left based on voltage. On one of my bikes i have the percentages written on a laminated paper on the handle-bar. I think with a 60v nominal battery this should be:

100% 67.2 v
75% 62.4v
50% 57.6v
25% 52.8v
0% 48v

but... sounds like there's something wrong with either the battery or something. you should definitely get more than 20 miles from a 20 amp-hour 60 volt battery. I would expect 30 - 45 miles out of that, depending on riding style. I assume you mean 20 amp-hour when you said 20 amp.
 
If it is standard Li-NMC (18650's or 21700's with charge ranges of 3.0v-4.2v) these charts will be accurate for the charge levels.


You mention C and P settings... is this a KT hub motor controller?
m@Robertson, I have been using your charge charts. Thankyou! I was just noticing that they appear to show a linear realtion between percentage drain and voltage. While this is *sufficiently* accurate for most users, myself included, it sort of technically isn't, right? If i have a nominal 72v battery which starts at 84v and drains to 60v, that's a delta of 24v, half of that mean's 72v is the half-way water mark in the voltage span, but the watt-hours remaing as i drain from 72v down to 60v are fewer than the watt-hours i had going from 84v to 72v because watts = volts * amps. I suppose how one reads "percentage" is a bit subjective, but i feel most people read these charts as "gas left in the tank".
 
Yes, 20ah. As I said in my first post, the vendor has been zero help since I got the bike. The original problem was that the bike was sent with the wrong display, it took them over a month to figure that out. When I was finally sent the correct display, the C and P settings don't seem to be correct. After another 3 weeks of emails and vmails, asking if one of their Techs can help, I have given up. Anyone have an ECELLS 5 STAR bike? If so, can you send me your C and P settings?
 
Unfortunately there are so many different proprietary small company ebikes out there that it can be difficult to find someone with advice on your particular system on this forum. Unless you're using the more common manufacturers like bafang, there are just too many of the smaller companies out there. I've never heard of ecells 5 star, and i have no idea what you mean by c and p settings. Batteries are a bit more universal.
 
I am guessing you may have heard of the WIRED ebike company? They produce a bike called the Freedom, with nearly identicle specs to the Ecells. On their website they talk about the necessary display settings, the C and P settings, to get the controller to talk with the battery and motor. There are a few Youtube video's that address the need to "match up" the correct parameters using the advanced setup in the display configuration. I guess I assumed most ebike's have that ability, I had an LectricXP from 3 years ago that did.
 
I will toss in one other problematic variable. With Goat bikes, they have some batteries which are true 60 Volt lithium ION cells, which are in series strings of 16 cells (16s). The battery in the Motor Goat v3 is also called 60 Volt, but it is a string of 17 cells (17s). It is really a 63.75 Volt pack, as versus a 60 Volt pack. This means the voltage for "full" on the 17s pack is 71.4 volts, and its dead level is higher than the dead voltage on the 16s pack.
 
If anyone is curious, this is a pic of the setup menu in my display.
 

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m@Robertson, I have been using your charge charts. Thankyou! I was just noticing that they appear to show a linear realtion between percentage drain and voltage. While this is *sufficiently* accurate for most users, myself included, it sort of technically isn't, right? If i have a nominal 72v battery which starts at 84v and drains to 60v, that's a delta of 24v, half of that mean's 72v is the half-way water mark in the voltage span, but the watt-hours remaing as i drain from 72v down to 60v are fewer than the watt-hours i had going from 84v to 72v because watts = volts * amps. I suppose how one reads "percentage" is a bit subjective, but i feel most people read these charts as "gas left in the tank".
If you read the text on the right side of any of the charts, I address that topic directly. Plus also I mention to be truly accurate you need to factor in the discharge curve of the individual cell types in your pack, and gave a link to a site where most of those curves can be found.

But thats a level of precision that for almost everyone is overthinking things. All you really need to know is you have X volts, and at Y volts if you touch the controller's Low Voltage Cutoff value, you are going to get shut down, and so you alter your behavior accordingly. When you see yourself getting close to the low water mark your brain will kick in and you decide what to do next. A chart is great for sitting at your computer and using as a general reference, but its not something you can whip out and use while in the saddle zipping along in traffic.

Take a look at the 36v, 48v and 52v charts. On those, I include a "Usable Volts" column which gives information along the lines of what you are looking for at 72v. But this value will change depending on your BMS' low voltage cutoff, and most likely will be further altered by how much your particular pack sags. Those issues bring individual pack and controller characteristics into the mix ... and pretty much toss out the idea of being able to use a chart created by someone who is not you.
 
KT controller, KT 8HU display, Hentach motor
Thats pretty straightforward stuff. So your pack is Li-NMC, which is commonly referred to as li-ion, but li-ion is sort of a blanket term that covers a lot of chemistries including LiFePO4.

The charts I linked will be accurate for your pack.

I use KT controllers on all of my hub motors so I'm familiar with all of the settings. If you want to read a KT manual written by a native English speaker, go here


Scroll down until you see the KT-LCD3 manual and click on that. KT settings are universal with a couple of very minor exceptions, and an LCD8 is effectively just a color LCD3 with the screen data rearranged. One thing that manual is missing is KT did not admit to the existence of C5=00, C5=01 and C5=02 even though they have always been live. C5=0 is full amps (like C5=10) but with maximum slow start. As in a gentle ramp up of power. 01 and 02 are also full amps with incrementally less slow-start applied to the curve.

The P5 setting is what you use to try and get the battery indicator to be more accurate. Good luck with that. There is an auto-sensing setting (0) that never seems to work. Yours is set to 8 which is really low. But... unless you like to tinker a lot you should consider time dicking around with that setting to be a waste of effort. You have a numeric voltage gauge which is a boon many displays do not provide. Use it. Learn what the volts mean from the linked charts. Its the only accurate measurement you can ever expect to have.

A 20ah battery on a 60v system is not all that big. Generally, people running 60v systems are also running pretty hard compared to a 52v or 48v system. If you have a high power bike you tend to take advantage of it, and as such you can expect less range.

I don't think anything is wrong with your system and the only thing that for sure is off is the P5 setting. Beyond that you will want to know if your P1 setting is accurate, which I sure would hope your bike manufacturer can be trusted to put in the correct value. Specs from Hentach will give you the magnet count and reduction ratio.
 
I see from your other thread you have an Ecells 5-Star bike. That bike advertises it is using a 40a controller. So to me that confirms what I said above about how a 60v system tends to get beat like a rented mule, and battery range can be expected to suck accordingly. You start flogging that battery with a 40a draw and yeah of course your range is going to be low. Especially with C5=10... thats fun but it can be expected to suck the life out of the battery.
 
m@Robertson, thx for the great information, certainly more than I have seen since I have been searching. You are right, nearly being thrown off the back of the bike is fun but I am sure it sucks the battery pretty quickly. I have been trying to find settings that allow me to peak around 750w and have a more slow ramp up of power. Right now its either off or full afterburn. Thx again for your help, much appreciated.
 
m@Robertson, thx for the great information, certainly more than I have seen since I have been searching. You are right, nearly being thrown off the back of the bike is fun but I am sure it sucks the battery pretty quickly. I have been trying to find settings that allow me to peak around 750w and have a more slow ramp up of power. Right now its either off or full afterburn. Thx again for your help, much appreciated.
I find that using "cruise control" on my various eBikes gives me the best energy economy, and avoids bursts of higher power consumption. Not all eBikes have this feature, but almost all the newer eBikes do.

For many eBikes, around 20 MPH seems to be the sweet spot for getting to a destination quickly, and preserving range.

For those who feel the "need for speed", multiple battery packs is a decent overall solution. But on those faster 40 MPH eBikes, you are likely talking 45 Amp Hour of capacity, or more.
 
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