A 48v battery is fully charged at 54.6v. The low voltage cutoff is around 39v. It is best not to discharge more than 80% of the capacity for good cycle life. 80% DOD is around 43v depending on cell chemistry. Li-ion has a flat discharge curve. The voltage will drop from 54.6v down to 50v fairly quickly then level off. Below 42v the voltage drops off quickly and there is not much remaining capacity left. The cells heat up at this point as well.
48 Volt (13S) Battery Voltage Chart - Li-Ion Batteries
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40buickcoupe
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very good information intresting bpth my batteries will only fully charge to 54.4 volts
CloneWerks
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54-ish Volts is the common "cut off point". There is some variation depending on the age and cycles of individual cells inside the pack.
JerryB
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Here ya go.....
Li-Ion Ebike Battery Charge Charts
Whats an 80% charge on a 48v battery? These charts give answers to questions like this on common ebike battery voltages: 36v, 48v, 52v, 60v and 72v.
talesontwowheels.com
40buickcoupe
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Anton do you have the chart in a PDF or a excell format you could send me?
I've just created a theoretical chart here which you should be able to copy into excel: https://ebikesforum.com/resources/48-volt-13s-battery-voltage-chart-li-ion-ebike-batteries.37/
40buickcoupe
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thank you worked great
Lotta Life Lefty
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I have recently purchased two 48v ebikes. When the charge is complete (green light on) I have checked the voltage on the display and on both bikes it reads 53.4v.
The chargers that came with the bikes say they are 54.6v and 2amp...
I am a bit confused as I have read and seen numerous charts that 54.6v is 100% charge on 48v ebike batterys, yet I see the chart above that indicates 53v is 100% charge which corresponds with my ebike readings.
Any clarification would be helpful...
Thanks!
Smaug
Well-known member
48 V is the nominal voltage. The actual battery voltage will vary depending on state of charge and what its load is at that moment.
As you noticed a 48 V battery at full charge with no load is more like 53 V.
If your display will show instantaneous voltage, you will see it sag down when you give it some throttle, then it comes back up when the load is removed.
Example: I was out riding my 52 V-rated eMoped last night. It was at around 54 V when I left, so not quite fully charged. When I hit the throttle, I noticed it sag down to around 49 V. I didn't notice the no-load voltage when I was done with the ride.
Anton provided some voltage charts that correlate state-of-charge with no-load voltage measurements; search them up if you're curious.
Have a look at my other 48V battery chart here which shows 54.6V as 100%: https://ebikesforum.com/resources/48-volt-13s-battery-voltage-chart-li-ion-batteries.37/
Calculation: 13 Cells x 4.2 Volts/Cell = 54.6 Volts Fully Charged
Assumptions: Your pack uses typical 18650 cells which charge to 4.2V and discharge to 3.0V.
