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I learned about statistical methods of quality control (acceptance sampling) in 1969 or 1970. The math wasn't new, they existed back in the 1020s. We were taught Poisson, Bernouilli and Bayesian statistics and the Japanese production methods were always cited as examples. What they did was...

Close enough is good. You can adjust the gap with extra washers or another cable tie saddle. Send some pictures to Andy.

When was the last time you saw a pack out of balance? If you consider everything, would you agree that lower voltage equals also to lower fire risk beside longer life?

Email Andy for the seat post mount and a new magnetic ring, you already have the sensor.

I disagree with that conclusion. How often your battery is completely flat in the last 5 years? Statistically, people put their battery on charge far too soon for fear of running out on the next outing rather than when their battery is flat. Charging when the battery is 80% or more full does not...

Saneagle's test is much easier to understand compared to Padja's though. Saneagle also explains the point in plain English. You may lose up to 3% of capacity if you charge to 4.1V but you gain in longer battery life.

thank you @saneagle. I reckon your BMS is similar to mine, it won't charge the cell above 4.15V. We lose only a small amount (3.1%) of charge between 54.6v (4.2V per cell) and 53.3v (4.1V per cell), and less than 1.5% between 4.2V and 4.15V.

there are lots of reasons why a low step bike is the right choice, independent of your gender: 1. You have a child seat on top of the luggage rack 2. You suffer chronic back pain 3. You like the Dutch riding style and their swept back handlebars

They are just generic. I have not seen a single battery needing rebalancing for a few years now so my experience with this issue may well be not up to date.

I will remind you, but remember, I am interested to know what the charger consumes when the voltage at the output is above 41V. My SANS charger does not let me do that above 41.3V

usually 41V but you'll know if you watch the energy meter, balancing consumes about 3W-5W on the meter. Now and then, it may spike to 10W-25W for a few seconds, the LED on the charger will flash red. If your battery is already balanced, the LED on the charger will simply goes from red to green...

Stuart's battery is practically brand new. I doubt that the bleed accounts for much in his experiment. Next time you charge your battery, check the power consumption when output voltage is between 41V and 42V and let us know what you see.

The SANS charger we use gives only up to 41.5V at the output port. If you ask have I seen 42V at the output on a 36V battery then the answer is no. I have of course tested batteries many times in the past.

just a brain fade moment. I see the numbers but somehow the brain registers something slightly different. In this case, I saw 4.1V and my brain does not go 10S=41V but 41.1V. Usually, a colleague will touch my shoulder and point at my mistake. The alarming thing is brain fade happens to me more...

Discharge curve: SAMSUNG INR271700-50E, stuartsproject's battery. Note: As you can see, if you pull hard on a full battery, the voltage will sag, you can't measure anything meaningful right away. However the top plot (@ 0.2A discharge current) is pretty good as representative. On the vertical...

I was mistaken, I thought you went from 41.1V to 41.2V. When I realised my mistake, I deleted that post. 41V to 42V is about 10%. Your 34 minutes are ball park figure.

Did you measure the 1.12Ah with an energy meter? If you did, you will have to deduct the conversion loss in your charger, the final amount will be about 0.9Ah or 9% of the capacity of your 10Ah battery.

that is correct but it's because it's more difficult to push the same amount of Lithium into an electrode that is already 90%-95% full. Its internal resistance to charging goes up when it is getting full. If you watch the amount of energy usage of a typical 36V 2A charger, you will see that it...

it can be up to 10% but I agree, the discharge curve is much steeper between 4.2V and 4.1V than between 4.1V and 3.5V where it's pretty linear.

I am intrigued by the 24%. I'll try to make a time lapse video about charging time / battery voltage/energy consumption over the weekend.