Selecting your solar charger / power station

What to consider when selecting a portable power station to charge with your pedal power bicycle generator system.  These are also called Solar Generators or Powerpacks There are a few major criteria that you will need to use to select your power station.

Things to consider

  1. Traditional lead acid  battery or lithium battery 

  2. The Amp hour rating (Battery Capacity)

  3. The max charge Voltage

  4. The max charge current

  5. Built charge controller or no built in charge controller

  6. The type of connectors needed to connect to the  power station

  7. Portability – how easy is it to carry around?  

  8. How long it will take to charge 

  9. Whether or not to use for both solar and pedal power.

  10. Number of charge cycles you want 

Lithium Battery

Pro’s of Lithium battery power stations:

  • Smaller and lighter than lead acid battery stations

  • Portable

  • Safe if the charge Voltage range is limited to a very low level

Cons

  • Can be unstable and get hot if charged with too much current

  • Safe batteries take longer to charge

We know that lithium batteries can be unstable if they are charged with too much current and get hot and can explode into flame. We know that Samsung phones were not allowed on airplanes for a period of time for this reason. The links below are affiliate links. This means that, at zero cost to you, I will earn a small commission if you choose to purchase.

Lower Price Point

An extremely safe and low cost way to use Lithium batteries in a power station/solar generator is to limit the charge current and charge Voltage range to a very low level.  For instance, the Jackery portable power stations are extremely popular on Amazon with 1000’s sold. Their prices can be under $500. 

Jackery Portable Power Stations

How did they minimize the huge risk of Lithium  battery danger?  They limit the charge current to around 3 Amps so that it takes 2 to 5 hours to charge their power stations depending which model you look at. 

Higher Price POint  

If you want to be able to charge much quicker, more efficiently, and use the full capacity of your bike generator or solar array, then you will need to spend more than $500 and get a power station that can handle 10 to 20 Amps of charge current and 0 to 100V DC  Voltage range. These are rare and expensive now but will be very cheap in 5 to 10 years. 

$200 - $1000 Lithium battery power station with built in MPPT charge controller power station that has built in features, then take a look at the items listed here. This will save you the cost of buying the NC25A  charge controller  because you won’t need it. 

Lead Acid Battery

Reasons for choosing a Lead acid battery style power stations are:

  • Very cheap

  • Not needing a portable power station

  • You want to charge with a lot of current 

Cons

  • Very heavy

  • Not many portable options

  • goes bad after a week if not kept fully charged

If you are on a tight budget you could use a very heavy lead acid 100 – 200AH 12V  marine deep cycle battery for around $100. You can also purchase one from your local automotive store.

This will give you the most capacity for the lowest amount of money.

If you need portability, consider a Low cost and low capacity lead acid AGM battery portable power station under $200.00 

Battery Capaticy

The capacity of a power station is based on a term called  “Amp Hours” or more often mentioned as “AH”. Many manufactures  hide their low AH rating buy putting it into the form of WH (Watt Hours). A 12V power station with a 10AH battery rating will be a 120WH rating.   (Watt Hours = Amp Hours x  12V Operating Voltage). So one can see that the number 120 is a much bigger than 10, and helps sell the product for the manufacture. 

For those who are not familiar with this term, here is a brief explanation:   

If you have a battery that has a 50 AH  rating then that means it can put out the following Amperage:

  • 50 Amps for one hour 

  • 25 Amps for two hours

  • 10 Amps for 5 hours

  • 1 Amp for 50 hours

In other words, if you want to know how many hours a battery power station or solar generator will last at a certain current or Watts, then you will need to divide the desired Amps output into the AH rating and that would give you the hours. For example, a 100 Watt DC bulb, running at 12V, will draw about 7 Amps of current. This is derived by using the equation, Amps  =  Watts / Volts. To solve for the number of hours, a battery will last powering the 100 Watt bulb at 7 Amps, we divide 50 AH  by  7,  and get about ~ 7 Hours.