REVIEW: QR-E 250W ELECTRIC BOOSTER BICYCLE MOTOR AND B60i AND B70 BATTERY

[Chazmo]

As always thank you for sharing your knowledge which has been very helpful to me and I'm sure many others based on the 145,000, and counting, views of this QIroll thread.
I'm still planning on riding the Mickelson trail this year, maybe next week if the weather forecast holds. Thunderstorm forecasts held me back from traveling there ealier but I have ridden on the Palouse to Cascades trail, in the north Cascades and over Going to the Sun road in Glacier so far this summer.
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Wow, beautiful, EMGX!

 

[blueberry]

Hi Blueberry, Thanks for showing up with tips.
At first i thought it was a screw in type of cap like water bottle or jar. Glad you shared about the info that it was lock on adhesive glue.

Question: Was the content inside tight fit with wires dangling about? Fear if i slid a thin blade between the gap it might touch the board or wires and ended up shorting the circuit. Hearing that you mentioned "the battery will end up with scratches" hinted that it was a tight fit inside and thin blade will swing nearby.

I don’t think you need to worry too much while you work on the adhesive in the gap, just be careful when you actually remove the lid. You also might want to make a mark on your blade (or feeler gauge like EMGX suggested!) the length of the cap, that way you know where to stop before it can curve around and towards the BMS.

 

[3dxl]

I don’t think you need to worry too much while you work on the adhesive in the gap, just be careful when you actually remove the lid. You also might want to make a mark on your blade (or feeler gauge like EMGX suggested!) the length of the cap, that way you know where to stop before it can curve around and towards the BMS.

Thanks for the tips, will do.

Reply for Qiroll Support:
Got reply from the support (Mr. Jason).

• Probably the probably 400W+ unit tested on with that battery was hit hard caused by over power consumption more than BMS can handle...still on test phase. Yes that battery was on Prototype Qiroll 400W+ unit.
• He says not recommended to disassemble or mod it (but i'll take the risk anyway).
• Will help out with after sales support on new battery (but i'll have to do few round with old H70 battery first with some test before i hit the shopping cart).

This week i will do a daily "trickle charging" on that problematic battery and do a few test run to see if i can restore to proper "power per mileage" performance before going through the blade under that cap. Will inform you guys about my findings.

 

[Chazmo]

This week i will do a daily "trickle charging" on that problematic battery and do a few test run to see if i can restore to proper "power per mileage" performance before going through the blade under that cap. Will inform you guys about my findings.

Excellent.

3, can you describe the equipment and process you use to do the trickle charging? Some of the other hobbyists have restored batteries (especially power tool batteries that they use for range extenders) by doing this. It sounds interesting, and I’m wondering about it. TIA.

 

[3dxl]

Excellent.

3, can you describe the equipment and process you use to do the trickle charging? Some of the other hobbyists have restored batteries (especially power tool batteries that they use for range extenders) by doing this. It sounds interesting, and I’m wondering about it. TIA.

This method applies to old battery: Since i have not open up the battery case of H70, here how i do it with supplied original charger;

1. Do normal full charge a drained H70 battery for 3~5 hours (depends how old the battery). When the Green LED lit leave it another 3 hours of continuous charging before pulling the plug/OFF.
2. Unplug the battery charger and leave it cool for 2 hours.
3. Then charge get back charging the battery again for another 3 hours. Its will start with RED led because of battery voltage still sagging. When the Green LED lit leave it another 2 hours of continuous charging before pulling the plug/OFF.
4. Unplug the battery charger and leave it cool for 24 hours (wait till the next day).
5. Then charge get back charging the battery again for another 1~2 hours. Its will start with RED led because of battery voltage still sagging (if the battery is old). When the Green LED lit leave it another 1~2 hours of continuous charging before pulling the plug/OFF. Done!

Assume if the BMS board inside the battery pack is good quality it should able to do "trickle charging" to balance the cell voltage.

*TODAY: Seems that problematic battery runs OK today as i ride to office again this morning, 2 LED bar lit without shut-off effect. But i haven't test on my way back home where i have to encounter some steep hill climb later evening.

However "if" i was able to open battery pack i could scan and target an individual battery to trickle or balancing charge the Li-on cell on by one with my RC model Smart Digital Charger before it hit lower that minimum storage voltage. Originally "Trickle charging" usually mean charging a battery that falls below 3.3v (For Li-po) or 2.5V (Li-on) by slow charging below 0.1 ~ 0.3A. However battery cell that already fall below its recommended voltage minimum/storage level won't last long and have short usable cycle before it bloats and blows a thermal getaway (burst/explode).

 

[Chazmo]

Thanks so much, 3xdl!

 

[3dxl]

Trickle Charge worked!

That problematic battery survived yesterday commute all the way through my journey and going up the hill using previously mentioned trickle charging method. Only experience "minus one bar"voltage sag but recovered back to two bar after reaching flat land and arrived home. Previous 2 days the battery was struggling but now is 'ok'. The only difference is the charging routine may take a bit longer and few trickling charging now and then. I marked that battery with "XX" labeling indicating 'suspicious' problematic battery pack.
Maybe its time to get new H70 battery soon as it show sign of deteriorating performance. This battery was on bike with 320W Qiroll Pro. On weekends it will be on killer 400W+ Qiroll folding bike.

 

[Chazmo]

Trickle Charge worked!

That problematic battery survived yesterday commute all the way through my journey and going up the hill using previously mentioned trickle charging method. Only experience "minus one bar"voltage sag but recovered back to two bar after reaching flat land and arrived home. Previous 2 days the battery was struggling but now is 'ok'. The only difference is the charging routine may take a bit longer and few trickling charging now and then. I marked that battery with "XX" labeling indicating 'suspicious' problematic battery pack.
Maybe its time to get new H70 battery soon as it show sign of deteriorating performance. This battery was on bike with 320W Qiroll Pro. On weekends it will be on killer 400W+ Qiroll folding bike.

A good feeling and I’m sure you saved yourself a lot of money in the process. Nice work, 3!

 

[EMGX]

Either an old eBay/AliExpress listing or their website, don’t quite remember where but they definitely said it somewhere. I also tried it out and it did work… personally I wouldn’t worry about overheating with the B70, except perhaps on steep slopes where performance would already be marginal.

FWIW I found a third party seller with a product description that indicated B70 battery compatible, no regen braking.

 

[EMGX]

In case anyone is interested
I noticed the top of my H70 battery was very slightly loose so it was easy to gently wiggle it off of the aluminum can. Here's what it looks like.


It wasn't as I expected, instead of glue all around the cap it looks like a strip of regular electrical tape with a couple areas of adhesive added on top of the tape to adhere the cap. What I could see inside appeared to be a layer of closed cell foam sheet around the battery pack as well as some expandable foam on top. The BMS is attached to the lid. Anyone know if the multiple wires extending to the BMS means that the BMS will balance the individual cells? My limited experience fixing electronic devices is that capacitors are often a cause of failure so if my battery has issues that'll be the first thing I check.

 

[3dxl]

In case anyone is interested
I noticed the top of my H70 battery was very slightly loose so it was easy to gently wiggle it off of the aluminum can. Here's what it looks like.
View attachment 198590View attachment 198591View attachment 198592View attachment 198593

It wasn't as I expected, instead of glue all around the cap it looks like a strip of regular electrical tape with a couple areas of adhesive added on top of the tape to adhere the cap. What I could see inside appeared to be a layer of closed cell foam sheet around the battery pack as well as some expandable foam on top. The BMS is attached to the lid. Anyone know if the multiple wires extending to the BMS means that the BMS will balance the individual cells? My limited experience fixing electronic devices is that capacitors are often a cause of failure so if my battery has issues that'll be the first thing I check.

Good job dismantling the battery, first time i see an Ebike battery with huge amount of foams and huge size capacitor. I've toying a lot on Hailong aka Bafang battery but the H70 one looks like some DIY stuff going on. Ironically H70 battery lasts longer than my Bafang battery.

Btw did you pull out the battery inside completely exposing li-on cell?

 

[EMGX]

Good job dismantling the battery, first time i see an Ebike battery with huge amount of foams and huge size capacitor. I've toying a lot on Hailong aka Bafang battery but the H70 one looks like some DIY stuff going on. Ironically H70 battery lasts longer than my Bafang battery.

Btw did you pull out the battery inside completely exposing li-on cell?

I wasn't planning to disassemble the battery so I didn't pull the pack out of the aluminum can mostly because of the expandable foam mess. Really I only removed the top cap because it was slightly loose and came off easily with a careful wiggling. It seems like it should be easy enough even for a cap that isn't loose. Yours and blueberry's battery posts made me curious.
Related to battery, I picked up a 40-90v to 36v buck converter so I can run my Pro on a small 48v battery that I have sitting around.