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Re using 2 Schottky diodes, one thing I only briefly mentioned is the delay in the green light coming on. In the example given in graph above, it will be noticed that although the forward voltage is .6v at 2 amp, this voltage is lower and is .4 volt at .2 amp which is about 10% of the chargers...

No. You have already saturated ( and stressed) the cells at 4.2 volts before you dropped the voltage and anyhow, with a little imagination, you do not need to modify the charger.Just get a matching plug and socket along with diode and heatsink and container as below. The diode can be used or...

Some charger can be adjusted. But there is a cheap hack that works without doing this (but not perfect). That's to put one (or two) schottky power diodes in series with the charger DC power lead to the battery. The diodes can be easily switched to short out so you can have either 2, 1 or none...

Just to mention something that Padja is suggesting in his ES testing. Cells come in different qualities when it comes to cycle life. Some are top quality ,some are medium quality and some are poor or of unknown quality e.g unbranded cells. He seems to be suggesting that good quality cells such...

Stuart, look at the graph below and see what you think of it. The Samsung is under charge at 1 Amp. At approx 237 minutes, it has reached a voltage of 4.1 volts (red line) and has reached a capacity of 4 Ah (blue line). If cell is allowed to go to full charge (315 minutes),it will have reached a...

I am inclined to wonder if charging a battery can be compared to cooking a chicken. The chicken can be crispy and brown on the outside but frozen on the inside. The chicken needs time for the temperature to get to the center. The cells also need a bit of constant voltage/floating/saturation time...

Stuart, try this experiment . 1. Charge your battery to 4.1v and immediately disconnect charger and immediately record the voltage. Wait 1 hour without turning on bike and record the voltage again. 2.Go for a spin on your bike and run down your battery. Enjoy. 3.Charge your battery fully to 4.2...

That can give very unpredictable results. The battery voltage will almost certainly start to fall unless the charge current is very small. There is a difference between (1)setting the charger to 4.1 volt/cell and (2)interrupting the 4.2v charger at 4.1v/cell. In the former case, the charger...

Interesting result. On the surface, there appears to be a difference between your figures and Padja. However, when you dig down into Padja figures, he uses the spec of 2.5v to 4.2v @ .2c as a reference point. This figure seems to be compared to his test usage which is 3v to 4.15v @ 1c to get his...

Seen as the original poster want to open a Pandoras box, it seems that 'memory effect' is still possibly a factor to be considered. It has been suggested below that some cells charged on lower voltages to extent their lifetime benefit from a full 4.2v charge every now and again as it recovers...

The action and explanation really takes place on the charge curve and not the discharge curve. A battery spends longer on the charger when charged to 4.2 volts and gets saturated with more electrons during the constant voltage saturation phase. More ions or whatever (I am not a chemist) are...

There is a long running discussion on 'Li-ion cells cycle ageing' on endless sphere. Although they have demonstrate that cell life can be extended considerably by reducing the 'Depth of Discharge' by keeping the cell working in the range 3.4 to 4.1 volts, they have considerably reduced the...

The original Raleigh all steel Bikes were considered a bike for life. They came with chainguards, 40 spoke rear wheel, long mudguards, steel frame, leather saddle and they did last a lifetime. But I am not sure if people and perhaps sellers are really interested in long life stuff any more...

Dont forget that there are good reasons for using the full voltage range for cells. Restricting the voltage range to multiply the battery life can considerably reduce the actual available battery capacity and range of the battery. For example, when endless sphere tested the Samsung 50E at 4.1...

Data sheet attached below. Not tested at 4.2 volts as far as I can see. I did read some speculation somewhere that the normal 500 cycles would be expected at 4.2 volts. I just use a 42v charger with older style power rectifier/diode in series that reduces the voltage by a little over 1 volt.

Samsung do cells for Tesla powerwalls that are specifically designed for long service life (+2000 cycles @4.1v) e.g. 21700-33j. They are cheap but require either soldering of tabs or laser welding. But again, there is a tradeoff of weight versus performance/capacity versus cycle life...

If you connect the 48V motor to a 36V battery, the motor rpm will also drop proportionally so you end up with a normal maximum cadence that tapers off completely at about 80 rpm as the 36v version has a different winding, which I believe is the only real hardware difference between the 36V and...

If I may add to above, if you are replacing the display and controller, I think you also need to change the control cable. You may need an extra long control cable for the pendleton (especially with the larger frame size earlier version) as the cable runs down along the frame down tube and then...

I am just speaking personally here but I have found on longer runs that I need/like a higher level of assistance. So in my case, my original 400Wh battery was sufficient for 35- 40Km journeys, I now carry well over 1000Wh for 60-80Km rides. I suppose also my batteries (and indeed my leg...

I actually like the yose bag. I usually cycle with it half unzipped so that plenty of air gets to the controller. I have also made a bigger hole at the bottom that allows air in but no rain. (The controller is tied up higher in the bag) I can also put my hand down and feel/monitor the...