Showing posts with label Battery Management System (BMS). Show all posts
Showing posts with label Battery Management System (BMS). Show all posts

Wednesday, May 13, 2015

How to Build the SolN1 Portable Solar Generator for Safety



How to Build the SolN1 Portable Solar Generator for Safety

LaserSaber came up with the idea of a light-weight mobile solar power generator with his video on YouTube.


However, the original SolN1 is missing the controller, and that controller should be compatible with LiFePO4 batteries...

Also, if you use the flat LiFePO4 batteries, you really need a Protection Circuit Module (PCM) for charging the four (flat) LiFePO4 batteries.


Here's a video from John Strabismus where he has the LiFePO4 controller and PCM:



  
The charge controller is needed so that you do not overcharge the battery. If you overcharge the battery, the LiFePO4 batteries tend to swell up, and can emit some dangerous fumes. In the worst case, they can even catch fire.
 
The battery management system is required because combining batteries for total power can cause a discharge at different rates per battery. This can cause problems when charging, leaving some of the battery pack undercharged, and others overcharged.

Regarding sizing of the PCM module, John Strabismus says:
 


"The main thing to keep in mind with your PCM choice is the size of the inverter you will be running. LaserSaber chose a 150w inverter, fully loaded it will pull close to 15amps continuous and surge a bit higher, that's why the surge rating on the PCM is higher than needed, as the inverter starts up with load it will pull more amps briefly then settle to its load draw, so the 16amp PCM matches the 150watt inverter, if you go higher like a 200 watt inverter you will be over the 16amps draw fully loaded and this will more than likely cause the PCM to shut down the load , so using a 20amp PCM for a 200watt inverter will match the components better."

So, you should remember that the PCM chosen should be based upon the power of the inverter.

You can find the PCM circuit boards on BatterySpace.com:

------------------------------------  
  - PCM for a 150 Watt inverter:
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Protection Circuit Module (PCM) for 4 cells (12.8V) LiFePO4 Battery Pack at 16A limited  
Part Number: PCM-LFP12.8V16A

http://www.batteryspace.com/pcmprotectioncircuitmodulefor4cells128vlifepo4batterypackat16alimited.aspx


-------------------------------   
PCM for a 200 Watt inverter:
-------------------------------
Protection Circuit Module (PCM) for 4 cells (12.8V) LiFePO4 Battery Pack at 20A limited
Part Number: PCB-LFP12V25A


http://www.batteryspace.com/PCB-for-4-cells-12.8V-LiFePO4-Battery-Pack-at-20A-limited.aspx


or


Part Number: PCB-LFP12.8V20A
http://www.batteryspace.com/pcbprotectioncircuitmodulefor4cells128vlifepo4batterypackat20alimited.aspx

   ------------------------------------------  

The "Flat" type of LiFePO4 batteries can be found on AliExpress:
 

3.2V 20Ah A123 LiFePO4 Prismatic APP72161227 PHEV/EV/E-REV Rechargeable Battery      $33.88 each x 4
http://www.aliexpress.com/w/wholesale-a123-prismatic-lifepo4-20ah.html

3.2V 5C   20Ah
Nominal Voltage:    1.2V
Nominal Capacity:    20Ah
Size:    7x166x227mm       (.276" x 6.54" x 8.94")
Package Size:    10cm x 10cm x 5cm (3.94in x 3.94in x 1.97in)
Cell Weight:    About 496 g   (1.09 pounds ea.)
Cell Capacity (minimum, Ah):    19.6A
Charge voltage:    3.75V
Power:    Over 2,400 W/kg and 4,500 W/L
Continuous discharge rate:    5C 100A
Peak discharge rate:    20C 400A (10 seconds) 



The original SolN1 videos:

 DIY Build Session SOLN1 Portable Solar Power:
https://www.youtube.com/watch?v=7CUuqJDzo1U

 SOLN1 - Amazing all in one free energy portable solar unit:
https://www.youtube.com/watch?feature=player_embedded&v=hy9wT7Vvkdw


DIY Build Session SOLN1 Portable Solar Power
https://www.youtube.com/watch?v=7CUuqJDzo1U

SOLN1 - Amazing all in one free energy portable solar unit.
https://www.youtube.com/watch?v=hy9wT7Vvkdw


Real Time SOLN1 Making-of + Other Updates
https://www.youtube.com/watch?v=x2XwmnjnwH0

SOLN1 Version 3 - Solar made easy!
https://www.youtube.com/watch?v=7-Y5TvWpWoQ


SOLN1 Update - Testing the Mini Boostpack
https://www.youtube.com/watch?v=z0a-2Zcy-VI


Battery Free Solar! Real Time Solar - Nano BoostPack + SOLN1
https://www.youtube.com/watch?v=_io9YHKdbTw
 

  
SOLN1 25 Kit Build Video - 20Ah Version
https://www.youtube.com/watch?v=MUUwnMwRlTk