Levo Gen 2 We can not use all the power of the battery

[TLSP]

I have some experience on batteries and have been working with them for long time.
As most of us know, a lithium cell, 18650, can be charged safely up to 4.2v and discharged to 3v
In my 2021 turbo levo I checked the voltage battery in mission control when battery is in "its" very low level and nearly cutting but it is still 33 or 34v so we have some power remaining that can be safely used. I sincerely doubt than a 500Wh battery allows to use that energy, in my oppinion the are doing like some cars manufacturers, keeping that energy to maintain the range when the battery starts to loose performance.

 

[Tim1023]

As a battery expert, perhaps you can answer a non-emtb related question that's been bugging me for a while
How does a powerbank work when charging my phone? I imagine the charge in each like reservoirs of water. As such, the powerbank can only keep charging until it is down to the same level as the phone, i.e. can't keep charging until it is empty.
I'm sure I'm understanding something wrong here, so a correction would be much appreciated!

 

[TLSP]

As a battery expert, perhaps you can answer a non-emtb related question that's been bugging me for a while
How does a powerbank work when charging my phone? I imagine the charge in each like reservoirs of water. As such, the powerbank can only keep charging until it is down to the same level as the phone, i.e. can't keep charging until it is empty.
I'm sure I'm understanding something wrong here, so a correction would be much appreciated!

A powerwank stores the energy using the voltage they consider better for their desing and has an electronic circuit that coverts it to a constant voltage to charge the phone. It is not like having 2 batteries in paralel, that will be crazy. The battery bank output holds constant voltage all the time to allow the phone to charge. (That voltage, usually 5v or 5.3v) dont need to be the same as the phone battery because it has also an electronic circuit inside to charge its battery.

 

[Zimmerframe]

I have some experience on batteries and have been working with them for long time.
As most of us know, a lithium cell, 18650, can be charged safely up to 4.2v and discharged to 3v
In my 2021 turbo levo I checked the voltage battery in mission control when battery is in "its" very low level and nearly cutting but it is still 33 or 34v so we have some power remaining that can be safely used. I sincerely doubt than a 500Wh battery allows to use that energy, in my oppinion the are doing like some cars manufacturers, keeping that energy to maintain the range when the battery starts to loose performance.

Two posts in and you're heading for complainer of the day ..

If you have experience in batteries you would know that two things will be relevant ..

Once the voltage goes lower, you will have less power .. Levo owners complain about less power (as you did in your other post) .

The charge and discharge states are set to extend the life of the battery. The lower you take the charge of the battery in discharge, the less time/number of re-charges the battery will last .. If they set them lower and the batteries only lasted for 10 re-charges - people would complain ! It's about balancing the performance you can get from the battery with longevity.

 

[Tim1023]

Aha! So it's like a the "reservoir" of the powerbank is held higher than that of the phone and as such can drain until empty?

 

[aarfeldt]

Once the voltage goes lower, you will have less power .

Errr....no.
When the voltage goes down, the apms goes up, to deliver the same output.

 

[Zimmerframe]

Errr....no.
When the voltage goes down, the apms goes up, to deliver the same output.

True .. I did write that incorrectly/crapily !

More that as the voltage goes down it restricts the power it makes available to you via software. So imagine how much more they'd lower it if they did allow even lower voltages. As Amps goes up, there are limits .. In the Levo, 20 amps. So with a lower voltage you'd need a higher amperage - which you can't have - so less power.

36v * 20amps = 720w. As your voltage drops - your amperage limit stays in place, so your power drops.

On top of that you're also still going to have issues with lower and lower voltages with motor start current and efficiency will also be less.

 

[aarfeldt]

More that as the voltage goes down it restricts the power it makes available to you via software.

Sure...it's controlled via software, and power-output was "permanent" in one of the beta releases.
I like'd that...

 

[jim0905]

A powerwank stores the energy

Can't beat a good powerwank

 

[MrSimmo]

I have some experience on batteries and have been working with them for long time.
As most of us know, a lithium cell, 18650, can be charged safely up to 4.2v and discharged to 3v
In my 2021 turbo levo I checked the voltage battery in mission control when battery is in "its" very low level and nearly cutting but it is still 33 or 34v so we have some power remaining that can be safely used. I sincerely doubt than a 500Wh battery allows to use that energy, in my oppinion the are doing like some cars manufacturers, keeping that energy to maintain the range when the battery starts to loose performance.

Not sure if you're referring to the power output in general or after the battery/bike hits a certain amount of remaining charge %.

If the latter - this may be interesting, may or may not be useful:

Motor Firmware 7.4.2

Release date: 09/03/2021
Replaces: 7.4.1

Features

• More consistent power delivery over the full battery capacity, including increased output power at a low state of charge (below 15%)

 

[TLSP]

Two posts in and you're heading for complainer of the day ..

If you have experience in batteries you would know that two things will be relevant ..

Once the voltage goes lower, you will have less power .. Levo owners complain about less power (as you did in your other post) .

The charge and discharge states are set to extend the life of the battery. The lower you take the charge of the battery in discharge, the less time/number of re-charges the battery will last .. If they set them lower and the batteries only lasted for 10 re-charges - people would complain ! It's about balancing the performance you can get from the battery with longevity.

I decided to dont reply to the other post because I dont want to start a discusion that goes to nowhere.
The limit of 3 volt per series is a totally safe and very common. Until 2.9v is also of, lower limits is right that can affect the battery life but 3 volt is totally ok. If you cut 3.3 or 3.4v, yes you can extend the battery life also if you charge to 4 and cut 3.5 but who wants that, is totally silly except for the battery manufacturer, to pass the warranty period without any claim.

As Aarfled told you, usually, the drop of voltage is replaced by increasing the current to have constant power.

About my complain saying that the bike lost power after last firmare update. It is totally true and many people verified it. And it happens with battery charged 42v, nothing related to this. Please, dont mix the things.

I am happy with the bike and I expent a lot of money on it, I just look for how to improve it.

 

[TLSP]

Not sure if you're referring to the power output in general or after the battery/bike hits a certain amount of remaining charge %.

If the latter - this may be interesting, may or may not be useful:

Motor Firmware 7.4.2

Release date: 09/03/2021
Replaces: 7.4.1

Features

• More consistent power delivery over the full battery capacity, including increased output power at a low state of charge (below 15%)

Not exactly. I just wanted to share and know your experience about the battery remaining energy when the bike say it is totally flat.
Usually a 36v lithium battery is 30v when flat (very safe limit) but our bikes battery say is flat with 33v, still about 40w usable remaining (8% more or less)

 

[Zimmerframe]

I decided to dont reply to the other post because I dont want to start a discusion that goes to nowhere.

I'm not trying to be difficult. You said in the other post that if specialized had dropped the power to make things more reliable, we should complain ! .... They haven't , but as I said, your statement leads to a situation where people just complain no matter what the reason.

I also said that you can check your power. If you can still draw 20 amps, then they've not reduced the power. You'd rather just decide something rather than prove it.

They've just changed the power delivery to make it smoother. If that means your motor is more reliable then it's a sensible upgrade ? Yes, others have said the same, but most of them hadn't updated the application before they did the update, so they had their acceleration response reduced. Once they'd corrected that, it was ok again.

To be honest, I really can't believe I'm here again responding to the Spesh bashing. I said I wouldn't do it anymore, but if people are just complaining about any bike and it's systems irrationally, then I can't help but say something .. call me a knob ..

As Aarfled told you, usually, the drop of voltage is replaced by increasing the current to have constant power.

Yes .. and as I said, I didn't explain it very well . But the point is , you are limited to 20 amps - so as voltage drops you will have less power.

I decided to dont reply to the other post because I dont want to start a discusion that goes to nowhere.
The limit of 3 volt per series is a totally safe and very common. Until 2.9v is also of, lower limits is right that can affect the battery life but 3 volt is totally ok. If you cut 3.3 or 3.4v, yes you can extend the battery life also if you charge to 4 and cut 3.5 but who wants that, is totally silly except for the battery manufacturer, to pass the warranty period without any claim.

This is your opinion - but as you say at the end, in your opinion it's "Silly" .. but as you also say, it reduces the likely hood of warranty claims - because of the simple fact that it makes the batteries more reliable and last longer. Everyone charges differently, stores differently, abuses their bikes differently - they have to take this into account.

All companies do this. They've not done it to try to steal power from us. They all desperately want to be able to give more than anyone else because it gives them a commercial advantage. Some of the cells might be able to withstand a wider range, but from a commercial standpoint, they've deemed it not worth the risk.

If you investigate further, you'll find that Bosch have the widest spread and have taken the most risk. Shimano have the lowest spread and have taken the least risk. To say that any of them are just trying to withhold your power from you is ridiculous.

As you yourself have said :

in my oppinion the are doing like some cars manufacturers, keeping that energy to maintain the range when the battery starts to loose performance.

It's not so much they they're keeping to free it up later, but because of operating the battery in a safer performance zone, it means that it might drop 10% capacity in a year for instance, but it then won't continue to drop - it will stay usable for longer.

I don't know about you, but I'd rather have a battery I can keep and use for 2/3/4/5 years than one which gives me 10% more range for the first three months, but then drops off rapidly and I need to buy a new one every year.

If you're really upset about it, just hack the voltage limits and accept that your battery isn't guaranteed anymore.

Anyway ... I'm off to defend haibike from people who think that bikes have their own nanobot service crew on board and to prepare to defend the siryon when people complain that a 17kg bike won't go 200km's ..

Oh yes .. Welcome to the forum and glad you like your bike

 

[MattyB]

...The limit of 3 volt per series is a totally safe and very common. Until 2.9v is also of, lower limits is right that can affect the battery life but 3 volt is totally ok. If you cut 3.3 or 3.4v, yes you can extend the battery life also if you charge to 4 and cut 3.5 but who wants that, is totally silly except for the battery manufacturer, to pass the warranty period without any claim.

3V/cell would be a very aggressive cut-off voltage - look at the discharge curve on the average high power 18650, they are almost completely exhausted at that voltage...

Remember these bikes are being sold in all sorts of climates. In colder countries you could easily permanently damage the packs through over-discharge with a cut-off so low. The manufacturers are not brainless, they know they need these batteries to do hundreds of cycles so they are never going to do that. Given the Spec batteries are from memory a 10S4P configuration 33V at rest when discharged = 3.3V/cell off load seems an eminently sensible endpoint.

We did discuss this before I think...

The real Specialized charging thread. - EMTB Forums

 

[leftside]

I have a Decoy, but found this thread interesting. I was going to attempt to hack my battery to not cut out at 9% remaining, and try and go lower. I won't do that now

 

[Specialized Rider Care]

Not sure if you're referring to the power output in general or after the battery/bike hits a certain amount of remaining charge %.

If the latter - this may be interesting, may or may not be useful:

Motor Firmware 7.4.2

Release date: 09/03/2021
Replaces: 7.4.1

Features

• More consistent power delivery over the full battery capacity, including increased output power at a low state of charge (below 15%)

For any Levo 2019-21 or Kenevo 20-21 owner that has felt the power noticeably drop as you approach the end of a long ride, this latest motor firmware update (7.4.2) does make a difference.

 

[boBE]

Most electric vehicles warranty the $$$ battery for 8 years, warranty meaning that the battery capacity will not drop below 70% nominal capacity in that time. They do this by limiting full charge and discharge, just as Specialized (and the others) is doing. Btw, the warranty usually does not specify the owner will get a new battery, only one that holds more than 70% of nominal charge.

 

[chamaruco]

So specialized is stealing our energy, storing inside batteries that we'll give back as exhausted and they will recover it inside their new bike that we will purchase again ???wow!

 

[1oldfart]

I am no techie so my knowledge is limited.
I try to read to learn and understand a bit.
From memory i read if we would empty a battery
we could not recharge it simply.
So if this is correct on a good system the energy stops leaving the battery
when there is still some left.
Maybe the cutoff happens at 5% or at X amount but
it is a good thing, it happens by design.
I remember many years back engine would could off when
overheating and could only restart after 5-10 minutes of cool down.

 

[Utah Rider]

I'm going to sign all my posts with "power wank expert".