Sajeel
100 mW
Dear Endless Spheres
TLDR: Can I limit CC charge to 1.6A from the output of a step up converter? If so, how? Can I control when the step up converter goes from CC to CV? If so, how? Is it possible to use a DC source 40V @ 5A (200 W) as input to the step up converter, having the step up converter output 57.4v @ 1.6A (~92 W) to the batterypack? Or do I need a DC source with lower current to match the wattage from the DC source? What happens with the excess power when the step up converter goes into CV mode and provides tampered current? Does it dissipate as heat in the step up converter, or is it simply not a possible solution?
Long story short:
I'm building my first eBike. Overvolting a 48v/1000W system running overvolted with 14S5P Samsung 50G cells @ 57.4v (charging each cell to 4.1v).
Finding a suitable charger able to do this, while also being able to regulate or limit the current looks very expensive - I've looked at "The Satiator" from Grin Technologies, but as I mentioned - it's too expensive. I want to preserve battery cycle life by limiting the charge current to ~1.6A (0.33C), but being able to fast charge when needed also seems like a very usable feature.
I want to build my own charger using a step up converter, but I'm in doubt about what I need to look for when I also want the current to tamper towards full charge of the battery.
I understand that it has to with CV (constant voltage) and CC (constant current). CC takes place while the battery is at low to medium-high battery capacity while charging, and then CV takes over towards full charge and the current is tampered. How does the circuit know when to swap to CV? Can I limit the CC to ~1.6A while CC is taking place? Can I control when CV takes over?
E.g. If I have a DC source suppling a step up converter with 40V @ 5A (200 W) and the step up converter supplies 57.4v @ 1.6A (~92 W), where does the rest of the power go? - Does it dissipate as heat through the step up converter? Or will it simply supply a higher current to match 200 W?
What happens when the step up converter goes into CV with tampering current? Even more heat that dissipates through the step up converter?
I like this solution if I can make it work, because it allows me to fully charge the batterypack every now and then for a full balance charge.
I will list the questions again, for the sake of anyone willing to help and provide valueable information:
1. Can I limit CC charge to 1.6A from the output of a step up converter? If so, how?
2. Can I control when the step up converter goes from CC to CV? If so, how?
3. Is it possible to use a DC source 40V @ 5A (200 W) as input to the step up converter, having the step up converter output 57.4v @ 1.6A (~92 W) to the batterypack, or do I need a DC source with lower current to match the wattage between converter and DC?
4. What happens with the excess power when the step up converter goes into CV mode and provides tampered current? Does it dissipate as heat in the step up converter, or is it simply not a possible solution?
Sorry for all the newbie questions. I'm doing my first build, which you can follow here.
Any input is much appreciated, thank you!
// Sajeel
TLDR: Can I limit CC charge to 1.6A from the output of a step up converter? If so, how? Can I control when the step up converter goes from CC to CV? If so, how? Is it possible to use a DC source 40V @ 5A (200 W) as input to the step up converter, having the step up converter output 57.4v @ 1.6A (~92 W) to the batterypack? Or do I need a DC source with lower current to match the wattage from the DC source? What happens with the excess power when the step up converter goes into CV mode and provides tampered current? Does it dissipate as heat in the step up converter, or is it simply not a possible solution?
Long story short:
I'm building my first eBike. Overvolting a 48v/1000W system running overvolted with 14S5P Samsung 50G cells @ 57.4v (charging each cell to 4.1v).
Finding a suitable charger able to do this, while also being able to regulate or limit the current looks very expensive - I've looked at "The Satiator" from Grin Technologies, but as I mentioned - it's too expensive. I want to preserve battery cycle life by limiting the charge current to ~1.6A (0.33C), but being able to fast charge when needed also seems like a very usable feature.
I want to build my own charger using a step up converter, but I'm in doubt about what I need to look for when I also want the current to tamper towards full charge of the battery.
I understand that it has to with CV (constant voltage) and CC (constant current). CC takes place while the battery is at low to medium-high battery capacity while charging, and then CV takes over towards full charge and the current is tampered. How does the circuit know when to swap to CV? Can I limit the CC to ~1.6A while CC is taking place? Can I control when CV takes over?
E.g. If I have a DC source suppling a step up converter with 40V @ 5A (200 W) and the step up converter supplies 57.4v @ 1.6A (~92 W), where does the rest of the power go? - Does it dissipate as heat through the step up converter? Or will it simply supply a higher current to match 200 W?
What happens when the step up converter goes into CV with tampering current? Even more heat that dissipates through the step up converter?
I like this solution if I can make it work, because it allows me to fully charge the batterypack every now and then for a full balance charge.
I will list the questions again, for the sake of anyone willing to help and provide valueable information:
1. Can I limit CC charge to 1.6A from the output of a step up converter? If so, how?
2. Can I control when the step up converter goes from CC to CV? If so, how?
3. Is it possible to use a DC source 40V @ 5A (200 W) as input to the step up converter, having the step up converter output 57.4v @ 1.6A (~92 W) to the batterypack, or do I need a DC source with lower current to match the wattage between converter and DC?
4. What happens with the excess power when the step up converter goes into CV mode and provides tampered current? Does it dissipate as heat in the step up converter, or is it simply not a possible solution?
Sorry for all the newbie questions. I'm doing my first build, which you can follow here.
Any input is much appreciated, thank you!
// Sajeel