The BMS should balance at 4.2v each not 4.23 or 4.24v, either it isn't accurate of your meter reading is out.
Bike cutting out when battery on 3 bars
- Thread starter bikemerchant
- Start date
When I touch the probes together it gives a reading of zero. When I touched the ends of the 5V charger it gave 5.02-5.04 so that would suggest the reading is .02 to .04 too high, I assume.
Do you guys recommend riding at full speed or limited to 700W before the next reading?
Experiment and learn!
You know how to get back to fully charged and balanced now, so you can recover from almost anything that happens.
700W I barely use 120w riding my main bike and don't get out of PAS1, probably why so far I have got over 35 miles from my 288wh battery.
So it broke down again (limited at 700W).
Did 3km round trip with break in between, no issues.
Charged it (not fully) before my next trip, 7km. Parked for 2.5 hours and when I started it up it would fail once 50W or so was pulled, so got a ride home.
The strange thing is on measuring this morning (not done anything since the break down) the series are completely level (each at 4.01V)!
Unsure what this would suggest?
Did 3km round trip with break in between, no issues.
Charged it (not fully) before my next trip, 7km. Parked for 2.5 hours and when I started it up it would fail once 50W or so was pulled, so got a ride home.
The strange thing is on measuring this morning (not done anything since the break down) the series are completely level (each at 4.01V)!
Unsure what this would suggest?
Is the 50W a typo, for 50V or 500W? If not 50W is nothing.
Probably dramatic voltage sag telling the bms to shut off, probably as a result of high internal resistance in one or more cells.
Not really possible to fully diagnose without stripping to individual cells and rigorously testing each one.
If there is a fault elsewhere, which I would regard as extremely unlikely given what has been seen from the battery, I would in my own case, with it in front of me, devise tests to narrow down what is happening.
But remotely I think we may have gone as far as we can. I think you need to bite the bullet and either get a less demanding motor, or a high spec battery, or both.
Yes time for a new battery, does appear to sound like drastic voltage collapse esp as expected the cells are fake 35e's. Any over current will induce higher internal resistance and lack lustre to poor performance.
I over cooked my 29e dolphin batteries with the doomed GSM mid drive, after that they both suffered and the 50 odd miles range disappeared and became about 30 on low power PAS2. If I babied them in PAS 1 I could get 40 miles but eventually I retired them from ebike use after 6.5 years and now they are used to power some other equipment at 36v.
I also have various 18650 torches and a wildlife camera so old batteries are decommissioned by me and the good cells used for these.
I over cooked my 29e dolphin batteries with the doomed GSM mid drive, after that they both suffered and the 50 odd miles range disappeared and became about 30 on low power PAS2. If I babied them in PAS 1 I could get 40 miles but eventually I retired them from ebike use after 6.5 years and now they are used to power some other equipment at 36v.
I also have various 18650 torches and a wildlife camera so old batteries are decommissioned by me and the good cells used for these.
Not a typo, it was 50W.
Guess I will bite the bullet so, can you guys recommend a good quality battery for this bike that is not overpriced?
Want to get a genuine one this time of course!
Guess I will bite the bullet so, can you guys recommend a good quality battery for this bike that is not overpriced?
Want to get a genuine one this time of course!
It is more choose a supplier known to deliver what they say they will, and no choice but to pay what it costs.
A £300 battery will likely have you back in the same situation quite quickly.
I doubt one will buy a decent UK made battery with genuine brand cells unless from Jimmy's company at ebike batteries.co.uk. Otherwise one will be looking at genuine China brand cells if the seller/maker buys form a reputable reliable source.
Good china branded cells are sinowatt, eve & bak another very good cell producer that is part of the big few is Molicel from Taiwan.
Good china branded cells are sinowatt, eve & bak another very good cell producer that is part of the big few is Molicel from Taiwan.
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Billy Milburn a forum member makes and sells batteries, he is located In Durham. Last time he mentioned due to scarcity of getting genuine branded cells he was using genuine China branded cells but even those are now being snapped up as the next best option.
You could enquire with this guy, he's a forum member and has been building bikes and batteries for a few years now. A few of his satisfied customers have posted here. Tell him the spec of your bike and the fact you ride on throttle only, he may be able to help you.
Another member/customer of Bill's here, post #38. Ignore the guy mentioned at the beginning of the thread,i'm eff. not recommending him.
www.pedelecs.co.uk
Battery Repair & Recelling
Looks good Chris you will have to keep the forum up dated with their progress over the next couple of years, good to see you have got new cells all the same brand and not recycled mismatched ones. I haven't found much on them yet but looks like a China branded cell certainly one I have not...
www.pedelecs.co.uk
One of the last recent posts Billy made on here was that he was also using the BAK China cells as nothing else as available, it does appear that some of these cells are quite good value and are good for the current the are spec'd for. What isn't known is the life cycle but if one got two or three years use then the would be deemed good value.
Thanks guys, he said he doesn't ship to Republic of Ireland unfortunately.
Any recommendations for someone who can ship to here? Or even better operates here?
Any recommendations for someone who can ship to here? Or even better operates here?
A name that comes up is EM3EV, and I know from buying non- battery stuff that Grin (why wouldn't you want to buy from a company with a name like that?!) will ship anywhere, but they are Canada. But they know what they are selling intimately, just that balance of assurance vs cost raising its head again. Ebike.ca.
I have bought from Psppower for my 48V build, but that is intended for far lower demands than you need, so I can't say it would do for your bike.
Found a highly rated guy on adverts.ie - he doesn't have 3500mAh cells, just 3000mAh Panasonic NCR18650PF.
Said the total cost for a new battery to be built into my case (78 of the above cells) would be €455 without an new BMS, or €490 with a new BMS.
Interested to hear any of your thoughts on this, thanks.
Said the total cost for a new battery to be built into my case (78 of the above cells) would be €455 without an new BMS, or €490 with a new BMS.
Interested to hear any of your thoughts on this, thanks.