[HKJ]

Fujitsu AA HR-3UTHC 2450mAh (Black) 2019



Official specifications:

• Voltage: 1.2V
• Energy: 3Wh
• Nominal capacity: 2.45Ah
• Typical capacity: 2.55Ah
• Weight: 30g
• Cycle life: 500 cycles.
• Low self discharge: 85% after 1 year

Maximum temperature raise at different discharge currents: 1A:+1,0°C, 2A:+3,0°C, 3A:+5,2°C, 5A:+10,5°C, 7A:+15,8°C, 10A:+21,6°C,
This is a retest, I have tested these batteries before.











The two cells tracks nicely and capacity looks good.















Here I pulse a 1A current to measure internal resistance during discharge.



Conclusion

This looks like good quality NiMH batteries.



Notes and links

I am replacing my NiMH charger test batteries, they are from 2016 and some of them has a fairly high internal resistance. Some of the bad chargers I have tested have probably increased the deterioration rate of them. These will replace the EneloopPro, but I except to still use a EneloopPro as a example of an old cell.

How is the test done and how to read the charts
Compare to other AA/AAA batteries: Alkaline/NiMH/Lithium

[elecom]

 Сообщение от HKJ :

I am replacing my NiMH charger test batteries, they are from 2016 and some of them has a fairly high internal resistance.

The increase in internal resistance is primarily due to the shallow discharge of nickel elements and is an integral part of the memory effect known to you. To avoid this effect, it is necessary to discharge the nickel elements as deep as possible, up to the complete zeroing of their capacity. For this, for example, you can take a suitable flashlight and wait until its bulb no longer lights up at all and give the opportunity to extend this discharge for some more time until all the remaining energy has been discharged from the battery.

[HKJ]

 Сообщение от elecom :

The increase in internal resistance is primarily due to the shallow discharge of nickel elements and is an integral part of the memory effect known to you. To avoid this effect, it is necessary to discharge the nickel elements as deep as possible, up to the complete zeroing of their capacity. For this, for example, you can take a suitable flashlight and wait until its bulb no longer lights up at all and give the opportunity to extend this discharge for some more time until all the remaining energy has been discharged from the battery.

No, these where my test batteries, this means they have nearly always been cycles between fully charged and discharged.
You also have to be careful not to discharge the batteries too much, that will kill them fairly fast.

[elecom]

 Сообщение от HKJ :

You also have to be careful not to discharge the batteries too much, that will kill them fairly fast.

What I said above applies only to Ni-Ca & Ni-Mh energy sources. This rule of complete discharge from charge before installation on the charger is not really applicable for Li-Ion and other lithium batteries. Full discharge (zeroing) only for nickel. I have repeatedly had to restore expensive Anton Bauer Ni-Ca & Ni-Mh batteries by the full discharge method to '0 volts' with the subsequent continuation of the load before installing on the charger for 5-10 hours.
You can also consider very harmful high currents not only during a discharge, but also during a charge, due to which evaporation of moisture from the electrolyte occurs. This fact, also caused by increased heating of the interiors of the cells, causes a violation of the composition of the electrolyte (when there is a decrease in valuable moisture), followed by a deterioration of all characteristics.

[HKJ]

 Сообщение от elecom :

What I said above applies only to Ni-Ca & Ni-Mh energy sources. This rule of complete discharge from charge before installation on the charger is not really applicable for Li-Ion and other lithium batteries. Full discharge (zeroing) only for nickel. I have repeatedly had to restore expensive Anton Bauer Ni-Ca & Ni-Mh batteries by the full discharge method to '0 volts' with the subsequent continuation of the load before installing on the charger for 5-10 hours.
You can also consider very harmful high currents not only during a discharge, but also during a charge, due to which evaporation of moisture from the electrolyte occurs. This fact, also caused by increased heating of the interiors of the cells, causes a violation of the composition of the electrolyte (when there is a decrease in valuable moisture), followed by a deterioration of all characteristics.

I was writing about NiMH, especially my Eneloop.

[elecom]

 Сообщение от HKJ :

I was writing about NiMH, especially my Eneloop.

Yes, I have four exactly the same batteries from Fuji '2450', and also have Japanese eneloop Panasonic AA '2500' & AAA '750' and '1000', so I made a regular lamp box specially for their full discharge, which I used From a failed charger