Though battery chargers are not my usual review candidates, I recently obtained the new Nona-charger by Cottonpickers, known for being the maker of 'the world's smallest li-ion charger with display', and had to put together a brief review as I have been so impressed with it.
Initial Impressions:
Being a fan of chargers that give the user information about the condition of the cell and the charging process, I have found the Nona-Charger to be excellent in this regard.
The Nona-Charger is so named due to the fact that it offers nine different constant current charging outputs.
The World's smallest charger, was a bare bones, mini charger that some felt was not as neatly finished as it could be, however the lack of a casing kept the size right down.
With the Nona-Charger, Cottonpickers has implemented a custom made plastic housing to keep the electronics hidden and well protected. The case has been made using a Molten Polymer deposition 3D printer. The example I have is a pre-production sample and the final shipped versions will have a more refined casing using layers half the thickness to smooth out the build.
What is in the tin:
The Nona-Charger is supplied in a small round unmarked tin with an instruction leaflet.
Opening the tin lid shows the full kit
This includes two standard magnetic connection leads and a set of crocodile leads which cone with round gold plated magnets in their jaws.
Taking a closer look:
Looking at the top of the Nona-Charger shows the output current selector switch at the top with ten positions from off to 750mA. On the right is the display on/off switch, and to the left the USB plug for power.
On the right hand end there is the charging indicator light (which goes out when charging is complete) and underneath this the socket for your chosen charging lead.
Looking at the USB pug end
Output Modes and User Interface:
The Nona-Charger's current output modes are stated as being OFF, 50, 100, 200, 300, 400, 500, 600, 700 and 750mA. You can select a suitable safe output charging current for any size of li-ion down to CR2 and 10440.
The appropriate output current is selected by moving the slider switch to the appropriate position. You can also choose to have the numeric display on or off (personally I find that it is the display that makes this charger so good so I leave it on all the time).
In reality, the control circuit allows the output current to vary slightly between an upper and lower limit depending on the cell being charged. Measuring these gives the following actual output current values (min-max):
41-54
95-108
196-209
291-304
398-410
479-492
598-612
730-740
778-790
The 700mA and 750mA outputs are slightly higher than stated, but using these you will be happy of the extra output for faster charging.
An example of the charging characteristics of the Nona-Charger is shown here for the 600mA output.
(Graph courtesy of Cottonpickers)
Using the Nona-Charger
To use the Nona-Charger there are a sequence of steps:
1. Attach the magnetic contacts to the battery terminals according to the lead colour. With the display on you will see the battery voltage.
2. Choose the desired output current.
3. Plug into the USB socket.
4. Wait for the green light to go out (4.2V will be shown on the display before charging is complete).
5. Unplug the charger.
6. Disconnect the battery.
This sequence stops accidental shorting of the charger leads.
The actual instructions are shown here:
While charging, the display shows the actual terminal voltage. During charging you can watch the battery voltage rising until it reaches 4.2V at which point charging slows down while the final topping up completes. The Nona-Charger has 4.2V set as the maximum output voltage and does not go over this.
Once fully topped up, the charger stops charging and switches off the charge light. At this point the display shows the off-charge voltage. You can get an indication of battery condition/quality by seeing what the voltage drops to once taken off charge. Of course the display draws a small current (around 20mA) but this actually helps to show the health of the cell as if the voltage drops quickly once off-charge, the cell is showing its age/condition.
The Nona-Charger shown ready to plug into a USB port with an AW 16340 protected cell ready for a top-up,
I would class the Nona-Charger as an 'enthusiast' charger. It is not for the inexperienced and not idiot proof, but like 'hobby chargers' provides the user great flexibility and precise control.
If you have multiple cells of the same type/age/model, the off-charge voltage, following completion of the charge cycle, allows easy matching of the cells.
Charging is fast and unlike any other dedicated li-ion charger I have seen, you are shown the actual terminal voltage so know how far along the charging cycle the cell is. This is so much better than a charger with red/green light which often continues to charge once the green light is shown.
I've been using the Nona-Charger with a computer USB port and a USB mains adaptor and have relegated all my other chargers to a drawer for backup purposes only.
A very impressive product for a 'cottage industry' business, and the Nona-Charger is now the only li-ion charger I use.
You can find the Nona-Charger over on CPFMP, just search for Cottonpickers.
Review sample provided for review by Cottonpickers.
I'll update post 2 of this thread once I have some more comments to add....
Initial Impressions:
Being a fan of chargers that give the user information about the condition of the cell and the charging process, I have found the Nona-Charger to be excellent in this regard.
The Nona-Charger is so named due to the fact that it offers nine different constant current charging outputs.
The World's smallest charger, was a bare bones, mini charger that some felt was not as neatly finished as it could be, however the lack of a casing kept the size right down.
With the Nona-Charger, Cottonpickers has implemented a custom made plastic housing to keep the electronics hidden and well protected. The case has been made using a Molten Polymer deposition 3D printer. The example I have is a pre-production sample and the final shipped versions will have a more refined casing using layers half the thickness to smooth out the build.
What is in the tin:
The Nona-Charger is supplied in a small round unmarked tin with an instruction leaflet.
Opening the tin lid shows the full kit
This includes two standard magnetic connection leads and a set of crocodile leads which cone with round gold plated magnets in their jaws.
Taking a closer look:
Looking at the top of the Nona-Charger shows the output current selector switch at the top with ten positions from off to 750mA. On the right is the display on/off switch, and to the left the USB plug for power.
On the right hand end there is the charging indicator light (which goes out when charging is complete) and underneath this the socket for your chosen charging lead.
Looking at the USB pug end
Output Modes and User Interface:
The Nona-Charger's current output modes are stated as being OFF, 50, 100, 200, 300, 400, 500, 600, 700 and 750mA. You can select a suitable safe output charging current for any size of li-ion down to CR2 and 10440.
The appropriate output current is selected by moving the slider switch to the appropriate position. You can also choose to have the numeric display on or off (personally I find that it is the display that makes this charger so good so I leave it on all the time).
In reality, the control circuit allows the output current to vary slightly between an upper and lower limit depending on the cell being charged. Measuring these gives the following actual output current values (min-max):
41-54
95-108
196-209
291-304
398-410
479-492
598-612
730-740
778-790
The 700mA and 750mA outputs are slightly higher than stated, but using these you will be happy of the extra output for faster charging.
An example of the charging characteristics of the Nona-Charger is shown here for the 600mA output.
(Graph courtesy of Cottonpickers)
Using the Nona-Charger
To use the Nona-Charger there are a sequence of steps:
1. Attach the magnetic contacts to the battery terminals according to the lead colour. With the display on you will see the battery voltage.
2. Choose the desired output current.
3. Plug into the USB socket.
4. Wait for the green light to go out (4.2V will be shown on the display before charging is complete).
5. Unplug the charger.
6. Disconnect the battery.
This sequence stops accidental shorting of the charger leads.
The actual instructions are shown here:
While charging, the display shows the actual terminal voltage. During charging you can watch the battery voltage rising until it reaches 4.2V at which point charging slows down while the final topping up completes. The Nona-Charger has 4.2V set as the maximum output voltage and does not go over this.
Once fully topped up, the charger stops charging and switches off the charge light. At this point the display shows the off-charge voltage. You can get an indication of battery condition/quality by seeing what the voltage drops to once taken off charge. Of course the display draws a small current (around 20mA) but this actually helps to show the health of the cell as if the voltage drops quickly once off-charge, the cell is showing its age/condition.
The Nona-Charger shown ready to plug into a USB port with an AW 16340 protected cell ready for a top-up,
I would class the Nona-Charger as an 'enthusiast' charger. It is not for the inexperienced and not idiot proof, but like 'hobby chargers' provides the user great flexibility and precise control.
If you have multiple cells of the same type/age/model, the off-charge voltage, following completion of the charge cycle, allows easy matching of the cells.
Charging is fast and unlike any other dedicated li-ion charger I have seen, you are shown the actual terminal voltage so know how far along the charging cycle the cell is. This is so much better than a charger with red/green light which often continues to charge once the green light is shown.
I've been using the Nona-Charger with a computer USB port and a USB mains adaptor and have relegated all my other chargers to a drawer for backup purposes only.
A very impressive product for a 'cottage industry' business, and the Nona-Charger is now the only li-ion charger I use.
You can find the Nona-Charger over on CPFMP, just search for Cottonpickers.
Review sample provided for review by Cottonpickers.
I'll update post 2 of this thread once I have some more comments to add....
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