Charging to 80% without a Satiator

DDBB

Well-Known Member
Not sure if you meant 3A ?!
3C charge would typically mean 10-12A for an eBike. Even 1C would make it warm and 3C would definitely make it hot!

Just to give you a perspective. Tesla supercharger is close to 1C and the charging cable definitely gets hot!
3C on any ebike for a few seconds would be ok but not many batteries are designed for sustained 3C draw.

For others who are reading this: 3C = you are draining your fully charged battery in 20 minutes.
Nope, I meant 3C charge... I do it all the time with lithium packs and they never get even warm. Of course these packs are rated for 70C discharge so they are very low internal resistance packs
 

KLee

Active Member
I enjoy the power of a topped off pack on my CCX. Does it make a difference (longevity wise) if I charge from 50% to 100% versus 30% to 80%? Does that still count as half a charge cycle since I’m only adding 50% charge?
 

Thomas Jaszewski

Well-Known Member
I enjoy the power of a topped off pack on my CCX. Does it make a difference (longevity wise) if I charge from 50% to 100% versus 30% to 80%? Does that still count as half a charge cycle since I’m only adding 50% charge?
So many of us waste time fretting over battery management. Heat, demands on the pack, and model of cells used all come into play. Do 80% when you can, learn what the LVC is (low voltage cutout). So many batteries get tired and saggy after 5 years. Do your best to keep it as cool as conditions allow.

Do the best you can but first off RIDE. Ride it like you stole it and have fun. Start a battery account. Going for a ride, throw a buck in the can. The can will be ready when the battery is.

From my experience, I find connection maintenance at peak. Small shorts can create hot spots and frying of connections. Shark packs with slotted connections is a good example. New connector sales are brisk.

I do understand the desire for real empirical data, there's just to many variables.I charge my 5-year-old batteries to full 100%.

My can is full... either a couple of new EM3ev soft (actually Paul uses a plastic shell.
packs or eBikes.ca modular batteries or maybe one of each type.
 

Jeff in WA

New Member
People like you a rarity. Most ebikers here on the forum are recreational riders not dedicated 30 miles/day commuters. So, what you mention makes total sense for someone who is wanting to get the best out of the battery and use it for 4-5 years under heavy usage.
For someone who is doing only 1500 miles to 2500 miles a year, these things may not matter much.
Not sure if that was a compliment or sarcasm. Yeah, things may not matter for some. But, my interest is engaging with those who like to explore and, as you say, want to get the best out of what they have. If that is a problem in this forum, just say the word.
 

KLee

Active Member
So many of us waste time fretting over battery management. Heat, demands on the pack, and model of cells used all come into play. Do 80% when you can, learn what the LVC is (low voltage cutout). So many batteries get tired and saggy after 5 years. Do your best to keep it as cool as conditions allow.

Do the best you can but first off RIDE. Ride it like you stole it and have fun. Start a battery account. Going for a ride, throw a buck in the can. The can will be ready when the battery is.

From my experience, I find connection maintenance at peak. Small shorts can create hot spots and frying of connections. Shark packs with slotted connections is a good example. New connector sales are brisk.

I do understand the desire for real empirical data, there's just to many variables.I charge my 5-year-old batteries to full 100%.

My can is full... either a couple of new EM3ev soft (actually Paul uses a plastic shell.
packs or eBikes.ca modular batteries or maybe one of each type.
Well said! I have been charging from 50% to 100% or 40% to 90% and enjoying the riding experience. I do not like the saggy motor response when the voltage levels drop lower.
 

ebikemom

Administrator
Staff member
Not sure if that was a compliment or sarcasm. Yeah, things may not matter for some. But, my interest is engaging with those who like to explore and, as you say, want to get the best out of what they have. If that is a problem in this forum, just say the word.
Jeff, we share your interests. Ravi's post isn't sarcasm. Heavy users who want to get out of what they have use different strategies than casual users. :) I also commute daily--25 miles. We are rarities! Like diamonds! :)
 
For me, if I can get 500 extra cycles out of my battery with this simple chart and a timer I yell at my living room Alexa, it's a no brainer. That's 15,000 potential miles and two years of commuting! That'll make my battery the longest lasting part of my bike besides the frame itself.
 

cellistpilot

New Member
Justin, with that profile pic you have to be a bubblehead. I'm one too. If you would like to chat let me know how to private message you. I've recently got an RCS. Which e-bike do you have?
 
Justin, with that profile pic you have to be a bubblehead. I'm one too. If you would like to chat let me know how to private message you. I've recently got an RCS. Which e-bike do you have?
I have to admit, I am. Pictured on the USS Kentucky in 2016 somewhere in the Pacific. I have the 52V CCS with Marathon Plus tires, an unfortunately rare combination between the CCS and CCX lines. My wife has a RCS.
 

DDBB

Well-Known Member
Justin; Can you hook us up for a short cruise on the USS Kentucky sometime? I would like a ride in a 2 billion dollar sub before I die
 

PastorDave

New Member
Have any of you math guys ever calculated an average minutes per volt charging guideline? ? For instance if I am at 43.3 and I want to go to 53.3...how long should I set my timer for? Or is this an oversimplification? (I have a 48/12 battery).
 

Thomas Jaszewski

Well-Known Member
Have any of you math guys ever calculated an average minutes per volt charging guideline? ? For instance if I am at 43.3 and I want to go to 53.3...how long should I set my timer for? Or is this an oversimplification? (I have a 48/12 battery).
Unfortunately that's not really possible because the Ah of the pack isn't linear to the voltage, that's why I go off of the nearest 5% per my calculations for the 52V pack.
 

Thomas Jaszewski

Well-Known Member
Unfortunately that's not really possible because the Ah of the pack isn't linear to the voltage, that's why I go off of the nearest 5% per my calculations for the 52V pack.
I'd have to differ. I have several customers that have sorted it and have run into many forum posters who also do. It may not be linear but apparently, the charge time from a given voltage to the goal is predictable. Adding a voltmeter makes it easy to sort.
 
I'd have to differ. I have several customers that have sorted it and have run into many forum posters who also do. It may not be linear but apparently, the charge time from a given voltage to the goal is predictable. Adding a voltmeter makes it easy to sort.
Yes, exactly. Because it's for a "given voltage" i.e. you know the pack's charge state at that specific voltage. You can't however say "I'm at (any voltage) and I want to add 2 volts, so 2 volts is always 1 hour of charge.

If you had some external meter I'm sure it's possible because it's constantly checking, but otherwise you're going to calculate the charge % or Ah, or use a chart.
 
Many users report getting close enough for most.
Let's break it down for PastorDave.

The vehicle for charging your battery is of course the charger, so let's start there. The chargers are rated for their output in Ah. The one included with most Juiced bikes is rated for 2 amps of continuous output, until the battery is at a certain level where it switches to a trickle charge. So for our purposes until it's charged, it's a steady 2 amps, and over an hour that means 2Ah of charge.

Next we'll look at how voltage related to Ah (we can measure charge state in Ah or Wh, which is Ah x Volts, but not Vh).

Now the next bit is an estimation based on the cells in your pack, this is from my own calculations. Everyone's, including Juiced Bikes' estimate, is slightly different.

Say my 52v battery is at 48.7 volts and I wanted to get to 56.3V. I want to "add" 7.6 volts. That's 12.27 Ah of charge by my calculation in the original post, divided by the rate of our charger at 2 amps, equals 6.135 hours. Each volt is roughly 1.61 Ah in this range. That's .8 volts an hour.

Now let's say my pack is at 54.2 volts - 13.28Ah. And I want to get it to 56.3 volts - 16.35Ah. I want to add 2.1 volts, which at these states of charge is 3.07 Ah. Each volt is roughly 1.46 Ah in this range. This will take 1.535 hours, or .73 volts an hour

As you can see PastorDave, you may be able to 'estimate' by splitting the difference at .75 volts an hour for a 52v pack, but personally I go by the actual Ah in the pack instead, and divide how much charge I want to have by 2, to give me exactly how many hours I want my bike to be plugged in.