Charger and Power Supply calculator


Finding the right charger and the right power supply unit (PSU) for the charger can be a difficult task. Because most chargers have more limits than just output power and more requirements than just input power.

We address this issue with the charger and PSU calculator below. All you need to do is enter the capacity and the cell count of the LiPo pack you like to charge. Furthermore the desired charging C rate and how many of the packs the charger should be able to charge in parallel.


The results of the calculator are the needed charger output power and current as well as the PSU output power and current.


KEEP IN MIND: The results can just be seen as a rule of thumb as each PSU and charger may have slightly different parameters. Therefore everything is without any guarantee. If you have found a possible error though please let us know and we will correct it right away.


Table with specific charger data


In addition to the general results we want to provide data for specific chargers as well so it is very easy to find a charger and a PSU that suits your charging needs.


The iChargers are claimed as the best when it comes to "value for money" and reliability at the same time.

The table let you know which iCharger suits your needs and which PSU you will need for it. In addition it gives you the maximum charging C rate possible.

Finally you can find the manuals of each iCharger when you click on its name.


If you want us to add a specific charger or brand don't hesitate to contact us - we are happy to add it to our table if possible.


One last word about PSUs: If you like the building part of our great hobby, a used PSU from a computer server is your best choice. You can get a 12V, 100A (=1200W!) PSU for ~60 USD if you are keen to modify it yourself. There are plenty instructions on the internet.

If you don't want to do it yourself DSW sells great, already modified and ready-to-use PSUs from private.


About parallel charging


Parallel charging has become popular due to the fast increase in power of the chargers. Instead of charging each pack separately, you can connect them in parallel and charge them all together. There are some important rules though:

• all packs must have the same cell count
• all packs and all parallel cells must have almost the same voltage/same charging state
• the packs can have different capacities
• use a save parallel board to connect the packs (one with fuses)
• if the charging state is slightly different connect the one with the lowest first
pay close attention when connecting packs


The charger itself doesn't know anything about parallel packs. It just sees one big pack. For example: Charging three 5000mAh 6S packs in parallel is the same as charging one 15000mAh pack.

A great education about parallel charging, as well as charging and LiPos in general can be found here


About the values of the calculator


General values of the calculator (valid for any charger):

capacity [mAh]: The capacity of one LiPo pack you want to charge.
cells per pack: The number of cells of the pack.
Remember: All packs must be the same cell count to charge them in parallel!
packs in parallel: How many of the packs do you want to charge in parallel?
If you want to charge packs with different capacity in parallel just add up their capacities, enter the result in the capacity field and '1' in this field.
charging C rate: The desired charging C rate of one pack.
charger power [W]: The charging power a charger needs to deliver to charge the pack(s) at the desired C rate.
charger current [A]: The charging current a charger needs to be able to supply to the pack(s) to charge them at the desired C rate.
PSU power [W]: The minimum output power of the PSU needed to supply one charger with enough power to charge the pack(s) at the desired C rate.
It takes a 90% efficiency of the charger into account.
PSU current [A]: The minimum output current of the PSU for three different output voltages (see '@...') to supply the output power.
Make sure the output voltage of the PSU is within the charger's input voltage range.


Columns in the specific charger table:

Each model has two rows. The first one represents your desired charging C rate. The second row shows the maximum charging C rate possible by the charger.

Charger: The model of the charger. Click on it to download the user manual.
charging C rate: The charging C rate of the current table row.
PSU power [W]: The minimum output power of the PSU to charge at the C rate given in the "charging C rate" column.
possible PSU voltage range [V]: The possible output voltage range of the PSU to charge at the C rate given in the "charging C rate" column and with the specific charger model.
For example a value of "16.8 - 38.0" means: The PSU needs to output at least 16.8V to the charger whereas a maximum of 38.0V is supported by the charger.
voltage-corresponding PSU current range [A]: The current the PSU needs to supply to the charger regarding to the voltage range.
For example a value of "16.8 - 38.0" for "possible PSU voltage range" and a value of "50.0 - 22.1" here means: If the PSU supplies 16.8V it needs to be able to deliver 50.0A at that voltage. If it supplies 38.0V it only needs to supply 22.1A.


Charger and PSU calculator


Enter the capacity of one LiPo pack, the cells per pack, the count of packs you want to charge in parallel at the same time and the desired charging C rate per pack. Finally press "Calculate".

To see a sample value of a field just leave it blank. To see a sample calculation just press "Calculate" with no values supplied.