The normal resting voltage for Eneloops is somewhere between 1.2V and 1.4V. During use, the average voltage is about 1.2 Volts.
So, why does my Eneloop charger stop charging at 1.6 Volts and sometimes at 1.45 V?
What is the maximum charging voltage for Eneloop?
That is normal behavior. It depends on the battery you charge, the charge speed, and how old/often it is used. But the ambient temperature also influences this a lot. If you charge a battery in a very cold room, your end Voltage will be higher than in a warm room. Also, keep in mind that the voltage will drop after it finished charging, so you usually don’t see the highest voltage unless you test it directly after the charge.
Please take a look at this graph below that is taken from a 4th generation Eneloop standard product sheet. You will see quite a difference in Voltage in relation to Ambient temperature.
The blue line almost reaches 1.7V when the ambient temperature is around 0 degrees Celsius. Many chargers have a cut-off voltage at around 1.65V.
When the temperature is 40 degrees Celsius, the end-voltage is much lower at around 1.55V.
More questions about charging (Eneloop) batteries
+ Is slow charging better than fast charging for Eneloops?
+ What do mA and mAh stand for? And what’s the difference?
+ How many times can Eneloop rechargeable batteries be recharged?
+ Do Eneloop batteries need a special charger?
+ How long do Eneloop batteries hold a charge?
+ What is the recommended charge current for Eneloops?
+ What’s the best Eneloop charger?
+ Eneloop Voltage – what’s the deal
+ Can you overcharge Eneloop batteries?
+ What is the maximum charge voltage for Eneloops?
+ Do I need to charge my new Eneloop batteries before I start using them?
+ Should I discharge my Eneloops completely before charging them?
+ How long does it take for Eneloop to charge?
+ How do I need to Refresh my Eneloops?
+ Can I refresh Eneloops if I don’t have a charger with a refresh option?
+ How many years do Eneloops last?
Advanced Eneloop charging info
+ What is -dV/dt charging? (termination)
+ What is 0 dV/dt termination?
+ How are Eneloops tested to claim a 2100 cycle life? (IEC 61951/ JIS 8708)
+ Non-charge related questions can be found in the Eneloop FAQ