Charger enhancer for PEV

[techyiam]

 

14 hours ago, Chriull said:

16 hours ago, techyiam said:

But stopping the charger is all I need. I set the POT in the charger to give me the highest voltage I would want.

Be aware that the pot in the charger is for adjusting, so likely designed for seldom use!

Thank you for your advice. I understand that it is a trimming POT for calibrating the maximum charging voltage. Unlike something like a volume knob in a classic radio.

14 hours ago, Chriull said:

Controlling the amount of balancing by the voltage is maybe not the best way. Balancing happens (mostly) during the _constant_ voltage stage. As the name implies there is only some marginal voltage change depending on many parameters (internal resistances, cell age, charging current, charge state, temperature, charger characteristics, ...) and could be, at least over time prone to not neglectable drifts.

My observation of cell balancing behaviour came from my experience with my S22.

My S22 came with two battery packs that reads out voltages that are always 1.2 V apart.

I even opened up my wheel to charge each pack independently with the stock charger. Pack 1 is always 1.2 V lower the Pack 2 once I turn on the wheel.

I would disconnect each pack in turn and charge each pack separately with the stock charger. They both charged up to about the same voltage.

I then connect both packs back to the wheel. Once I turned on the wheel, Pack 1 would go down in voltage and Pack 2 would go up in voltage, but the difference of voltage between the two packs are always 1.2 V. I am thinking that the voltage readout of one the pack's BMS is not calibrated accurately.

With this condition, when I charge up my wheel, Pack 1 never gets charged up to 100%. The charger stops charging when Pack 2 gets charged up to 100%, and meeting a certain declining charging current threshold.

Subsequently, I trim the POT so that the maximum voltage is increased. I then noticed that Pack 2 then charges above 4.2 V for more cells, and the cells in Pack 1 are getting charged closer to 4.2 V.

I kept increasing the charging voltage until Pack 1 get charged to 100%. The cells in Pack 1 goes above 4.2 V, and were cell-balancing discharging a lot.

Eventually, the charging voltage got high enough where some cells in Pack 1 were cell-balancing. And that is as high as I want to go.

 

The difference between the highest and lowest cell voltage readings of Pack 1 was 30 mV out-of-the-box. And 20 mV for Pack 2.

After some charging cycles over time, now the cell voltages differences is about 15+ mV for Pack 1 and 4 mV or 5 mV for Pack2.

The cell balancing did its job.

So I don't need much cell balancing for the time being. I thought with something like the Charging Buddy, perhaps I can lower the cutoff voltage to reduce cell balancing.

At least, that is what I am thinking.

[Chriull]

4 hours ago, techyiam said:

I am thinking that the voltage readout of one the pack's BMS is not calibrated accurately.

That's a pity - charger, bms and motherboard voltage measurements have to fit. Especially measurements of two paralleled packs beeing off is very bothersome:(

Kingsong should have thought on though calibration and/or a possibility for remote calibration as inmotion offers.

4 hours ago, techyiam said:

The cell balancing did its job.

So I don't need much cell balancing for the time being. I thought with something like the Charging Buddy, perhaps I can lower the cutoff voltage to reduce cell balancing.

If one monitors single cell voltages regularly there is nothing against skipping the whole or a part of the balancing.

[RagingGrandpa]

On 12/22/2023 at 6:45 AM, Forwardnbak said:

https://pidzoom.com/blogs/news/how-to-make-pev-charging-safer

Hmm, does anyone understand it yet? 

What's an example of one problem this solves? 🤔

So far I've only seen "I want to know the actual voltage and current flowing, and my charger doesn't have a display for it." 

Anything else?

[techyiam]

44 minutes ago, RagingGrandpa said:

What's an example of one problem this solves? 🤔

Chargers are not smart.

I suspect if the BMS's in battery packs are well designed, then the "Charger Enhancer" can provide an extra layer of protection. Proper designed BMS's already prevent the battery cells from over-charging.

For some wheels, like the V12, after being fully charged and cell balanced, the charger doesn't completely turned off. Even after many hours, the AC power meter would still show the charger continues to draw some current. But in that state, the charger of the BMS has already stop charging. Either the charging current threshold has been reached, and the charger stops charging, or the per cell maximum charging voltage of one cell has been reached and the BMS would stop the charging process?

For euc's we have today, I haven't seen any of my wheels BMS's going wonky. (But the oldest is still not much more than two years old.) So I am not so compelled to buy one, except for my case of wanting to have a more convenient way of controlling cell balancing on my S22.

However, for some other types of low cost PEV's, maybe there is a need where the quality of BMS's may be in question?

 

Furthermore, if there is a consensus that as the battery packs age, their BMS's become less trustworthy, and the "Charger Enhancer" had proven itself to be reliable, accurate, and durable, then for older battery packs, the extra layer of protection provided by the "Charger Enhancer" can become useful.

 

Edited December 23, 2023 by techyiam

[Bizra6ot]

39 minutes ago, RagingGrandpa said:

What's an example of one problem this solves? 🤔

Night display mode for minimal sleep disturbance 

[RagingGrandpa]

57 minutes ago, techyiam said:

For some wheels, like the V12, after being fully charged, the charger doesn't completely turn off.

Ok, so how does Charger Enhancer help? When should it turn off?

(I'm hoping someone who represents this new product might explain it to us.)

[techyiam]

44 minutes ago, RagingGrandpa said:

Ok, so how does Charger Enhancer help? When should it turn off?

(I'm hoping someone who represents this new product might explain it to us.)

I see.

You want to know how PIDZOOM exactly define "safe".

We do know that the BMS's on the wheels of late will stop charging once a maximum charging voltage threshold per cell as been reached by one cell.

We also know we can preset the maximum charging voltage.

But we don't know exactly how the Charge Enhancer decides to stop charging?

[mtl]

4 hours ago, RagingGrandpa said:

Hmm, does anyone understand it yet? 

What's an example of one problem this solves? 🤔

So far I've only seen "I want to know the actual voltage and current flowing, and my charger doesn't have a display for it." 

Anything else?

Would this device prevent a wheel from charging to 100%? Charging to about 97% would be nice to reduce the chances of over voltage when starting down a hill or braking hard soon after starting a ride.

[techyiam]

2 hours ago, mtl said:

Would this device prevent a wheel from charging to 100%? Charging to about 97% would be nice to reduce the chances of over voltage when starting down a hill or braking hard soon after starting a ride.

The argument here is that this function is also offered by the manufacturers' app or a third party app.

I can do that with my S22 using the Kingsong app to set the %SOC value.

Edited December 24, 2023 by techyiam

[Chriull]

4 hours ago, techyiam said:

The argument here is that this function is also offered by the manufacturers' app or a third party app.

I can do that with my S22 using the Kingsong app to set the %SOC value.

Great that KS managed this! And hopefully all new wheels implement such functionality.

But until then and with all the other still driven wheels such a functionality would be great! As i assume @mtlwould be highly interested in the charge enhancer exactly for this functionality!

10 hours ago, RagingGrandpa said:

Hmm, does anyone understand it yet? 

What's an example of one problem this solves? 🤔

So far I've only seen "I want to know the actual voltage and current flowing, and my charger doesn't have a display for it." 

Anything else?

It shows Wh,Ah and charge time. Worth mentioning is that voltage measurement can be calibrated.

Imho battery fires arise from aged/deteriorated cells and cannot be prevented by voltage or current restriction during charging. (Beside single cell overvoltage monitoring - which only the bms can perform)

From a li ion manufacturers data sheet (?or a manufacturers application note for battery builders?)  required safety measures were time restriction for each charge and charge stop once current drops below the recommended threshold.

Number two is implemented according to the manual (charge stop after current drops below 300mA), a simple shut off timer is not implemented.

6 hours ago, mtl said:

Charging to about 97%

Unfortunately the 300mA are not adjustable - this value would allow to stop charging in the 8x% and 9x% S(tate)o(f(C)harge) region.

In their section 6 they show the correlation between cell voltage and charge percentage shown by the wheel. Unfortunately they ignored that the correlation between voltage and SoC is only true once the cells rested without load or charge some 5 to 30 minutes!

During charge the correlation is off - the more the higher the charge current is!

So by voltage driven cut off one can only stop charge up to some 75-85% SoC.

At higher SOC the charging is already in the C(onstant)V(olltage) stage and the perfect cut off condition would be charging current dropping below some _settable_ threshold.

To reduce battery charge stress while still maximizing usable capacity a stop at exactly this stage change would be perfect - the saturation phase (CV stage) puts most stress on the cells with just a low increase of charge.

Besides this some more great things such a charge enhancer could perform:

Internal resistance measuring

Timing length of constant voltage stage

Premature charge stop detection due to single cell overvoltage condition.

This should cover imho the most important "old age" parameters to increase safety.

Data recording/logging for further analysis is never bad, too;)

Firmware is easily updatable? Or at all? There was no mentioning in the manual. Just the note that firmware will be further developed...

Modded Firmwares could be a great sales argument in such an enthusiast niche market;)

[Frolic0415]

Why does this not include all the adapters with the unit? Bit silly to have to buy each adapter individually for $15aud for something that already costs $130aud

[Forwardnbak]

12 hours ago, RagingGrandpa said:

Hmm, does anyone understand it yet? 

What's an example of one problem this solves? 🤔

So far I've only seen "I want to know the actual voltage and current flowing, and my charger doesn't have a display for it." 

Anything else?

All I want is to know that my charger definitely turns off overnight when I need to charge while sleeping.

This solves it great for me, It has cut charge every-night I need it to. With 6 kids I just want an extra level of safety even if the wheel can do it, this is another layer of insurance.  

Thats all I was after. It is simple for me to use and works great and I sleep easier. Easy $100 spent for me.

I also trust Bob and am happy to support his new venture out of hope that he grows to support EUC industry. 

 

 

[Forwardnbak]

6 minutes ago, Frolic0415 said:

Why does this not include all the adapters with the unit? Bit silly to have to buy each adapter individually for $15aud for something that already costs $130aud

I did think it was shipping with the adaptors but I only had a test unit so maybe it changed.

I do feel the AUD exchange rate pain :/ 

[Forwardnbak]

all this feedback I think is great. 

I am learning and I want to know what people think. 

 I thought it was a cool idea that may help people and I didn't know of any unit that could do this easily prior.    

[Frolic0415]

7 minutes ago, Forwardnbak said:

I did think it was shipping with the adaptors but I only had a test unit so maybe it changed.

I do feel the AUD exchange rate pain :/ 

On the product page there's only an option to pick a single adapter with the unit, unless they change it to include all the adapters then I won't be buying it unfortunately.

[Forwardnbak]

12 minutes ago, Frolic0415 said:

On the product page there's only an option to pick a single adapter with the unit, unless they change it to include all the adapters then I won't be buying it unfortunately.

Possibly its a cost thing? Im not sure?? 

I will pass on the feedback, I don't make it :/ sorry.

Not sure if the adaptors might be available locally? Jaycar? 

I also can offer a very small discount code of you decide (only 5%)  but I understand what you are saying.

Our exchange rate isn't great.  

 

 

[techyiam]

6 hours ago, Forwardnbak said:

all this feedback I think is great. 

I am learning and I want to know what people think. 

 I thought it was a cool idea that may help people and I didn't know of any unit that could do this easily prior.    

Your Inmotion V11 and V13 already have very good safe guards against battery related malfunction dangers. Perhaps Bob Yan can provide a counter-argument.

But if your euc is not an Inmotion, even if the charger fails to stop charging, the BMS would still prevent over-charging. If any cell exceeds the maximum charging voltage per cell, the charging will stop.

I am not seeing the extra protection benefits provided by the "Charger Enhancer" for the Inmotion V11 and V13 with the stock charger and stock battery packs.

What I see is a device that can conveniently display various electrical readouts to let the user monitor the charging process, and also to have control over the maximum charging voltage. If you are use a stock charger, I can't see how you would need another layer of over-current protection.

Edited December 24, 2023 by techyiam

[The Brahan Seer]

2 hours ago, Forwardnbak said:

All I want is to know that my charger definitely turns off overnight when I need to charge while sleeping.

This solves it great for me, It has cut charge every-night I need it to. With 6 kids I just want an extra level of safety even if the wheel can do it, this is another layer of insurance.  

It is very bad practice to charge overnight* when you are asleep (if the device is in your house or building you want to keep). This is because you probably won't be able to react in time, its debatable when fully awake.  Battery failures...

 

3 hours ago, Chriull said:

Imho battery fires arise from aged/deteriorated cells and cannot be prevented by voltage or current restriction during charging. (Beside single cell overvoltage monitoring - which only the bms can perform)

 Remember when a battery catches fire its a chemical fire and very quick, not an electrical fire. But only 30% of fires occur during charging. Really we all should be keeping our wheels in its own shed/fireproof area.  I appreciate this is not always practical or possible for many of us and we just take a calculated risk. I do consider this to be low. But I still never charge my wheel unattended or semi conscious.

Your choice. 

 

*the London Fire Brigade amongst others advise this. 

[RagingGrandpa]

5 minutes ago, The Brahan Seer said:

we all should be keeping our wheels in its own shed/fireproof area

Lots of information and inspiration about practical EUC fire safety is here at your fingertips 🙂

https://forum.electricunicycle.org/tags/fire safety/

 

2 hours ago, techyiam said:

What I see is a device that can conveniently display various electrical readouts to let the user to monitor the charging process, and also to have control over the maximum charging voltage.

Cool.

 

2 hours ago, Forwardnbak said:

All I want is to know that my charger definitely turns off overnight

Sounds like this feature then: 

4 hours ago, Chriull said:

implemented according to the manual (charge stop after current drops below 300mA)

So despite the unknown utility of charge-stop for rising current...

I've heard 3 specific benefits: 

+ Displays electrical measurements during charging.

+ Automatically disconnects the charger when current falls below 300mA. (Prevents unnecessary float charging.)

+ Can be configured for partial charging, by automatically stoping at a user-specified voltage.

[Forwardnbak]

Im learning heaps thanks all.

Am I wrong to think that this is an extra layer of protection towards all the items you suggested working properly all the time? 

I am not always sure that things do what they say? or work 100% correctly all the time.

So to add another layer in between for the nights/times I cannot 100% monitor the wheel.

Like I know my v13 can trickle charge for hours and no cell balance, the V11 is only ever a light on a charger and a value on an app, even at 100% the charger has stayed on longer than I like with the V11.

I just prefer if im caught  up with the kids to know it shuts off. 

I rarely charge overnight, but as a true commuter vehicle it might be necessary if a device can make it safe to do so?

 

 

[Punxatawneyjoe]

1 hour ago, Forwardnbak said:

if a device can make it safe to do so?

Doesn't this only eliminate one aspect of why battery's catch fire during charging? Isn't there many other reasons they do during the charge phase?

I'm asking because i don't honestly know. Also i'm not sure i would trust a device made in someones garage over the factory installed safety's from Inmotion a company with lots of money for R&D. I know everyone likes Bob but it's almost like the CEO of Audi left and is now a door to door salesman selling shamwows.

[techyiam]

4 hours ago, RagingGrandpa said:

+ Automatically disconnects the charger when current falls below 300mA. (Prevents unnecessary float charging.)

After monitoring my wheels: T3, V12, Abrams, S22, I am not even certain that overnight float charging is really a concern.

Both my Abrams and S22's stock chargers draws zero amperes after being fully charged, so do my e-scooters, and e-bike. This is according to the AC power meter between the AC plug and the wall outlet.  I have never seen them coming back on by themselves, within the next day. According to the S22 user manual, the charger must be turned off and back on in order for the charger to start charging again.

The T3 and V12 still draws a small residual current after being fully charged and balanced. However, if I unplugged the charger within a 12 hour period, I have never seen the charger start drawing current again above the small residual current within that short period. 

 

[techyiam]

2 hours ago, Punxatawneyjoe said:

I'm asking because i don't honestly know. Also i'm not sure i would trust a device made in someones garage over the factory installed safety's from Inmotion a company with lots of money for R&D. I know everyone likes Bob but it's almost like the CEO of Audi left and is now a door to door salesman selling shamwows.

I personally would give Bob Yan more benefit of the doubt than that. Bob Yan is one of the original founders. If I am not mistaken, he has a technical background. As you probably know, Inmotion has a lot of checks and safeguards when it comes to battery protection. I have seen quite a few different types of warning and other errors messages relating to battery faults. The wheel can even prevent the rider from turning on or riding. It is much more than just offering charging protection. When Bob Yan explains that Inmotion has a focus on safety, I have witessed it. On the other hand, the T3 tells me nothing. Now, as the battery cells are aging, I am getting more worry with my T3.

And in interviews, Bob Yan come across knowledgeable of the technical aspect of the wheels.

Having said that, it would be helpful if more detailed technical information on the Charger Enhancer is provided.

Edited December 24, 2023 by techyiam

[Punxatawneyjoe]

33 minutes ago, techyiam said:

Bob Yan is one of the original founders

In the recent interview with wheel good time, he stated that the company was not his and owned by someone else. How can you be an original founder and not have ny stake in the company?

33 minutes ago, techyiam said:

And in interviews, Bob Yan come across knowledgeable of the technical aspect of the wheels.

Interesting, could you point me to such an interview? I have seen a few of his interviews and have not seen him delve into the technical aspect in any so it would be great to see if that were the case.

33 minutes ago, techyiam said:

it would be helpful if more detailed technical information on the Charger Enhancer is provided.

 ^this, the information about the assembly process, components used, testing practices and any certifications these "charger enhancers" have . It would be good to know what the maximum allowable amperage that can be sent through it without causing failure as well. For me , it seems like adding an extra set of un certified electronics that adds to the potential for failure.

33 minutes ago, techyiam said:

I personally would give Bob Yan more benefit of the doubt than that

Which benefit are you referring to?  That the products he is peddling are legit because he has a "technical" background? Is he himself building these? I feel like there is a lot of unknown here and would air on the side of caution with any electronic product that is not UL listed or tested by any other independent company. I just would like more information before i would put my trust into it. It's claim to fame is rather vague. Bob Yan seems like a good guy and his interviews are informative, i just don't want him packing my parachute.

Edited December 24, 2023 by Punxatawneyjoe

[techyiam]

3 hours ago, Punxatawneyjoe said:

3 hours ago, techyiam said:

Bob Yan is one of the original founders

In the recent interview with wheel good time, he stated that the company was not his and owned by someone else. How can you be an original founder and not have ny stake in the company?

From the horse's mouth:

Quote

As one of the co-founders of InMotion, I was able to get involved with the negotiation process and have a bit more insight. I believe the EUC community deserves to know what happened in the past few years.

Source.

 

Bob Yan has a Master Degree in Mechanical Engineering.

Source.