Which 12V solar charger solution ?
-
Hello,
I'm currently using the TP4056 linear charger to charge a single cell lithium-ion3.7 V battery from a solar panel as explained here : http://www.instructables.com/id/DIY-SOLAR-LI-ION-LIPO-BATTERY-CHARGER/
However what i need is 12V rather than 3.7V for my project , and i still want the automatic solar panel recharge every day, so:
-
Either may be should i use a 3.7V to 12 V boost up module such as
http://www.ebay.com/itm/25W-DC-DC-3-3V-3-7V-5V-to-12V-Step-Up-Boost-Module-LED-Moter-Router-Power-Supply-/281237769996
but i have no idea what extra power consumption such boost up module implies for an output charge working at ~ 300 mA ... (on 12V) ... (i'm not so worried because the output charge (a solenoid valve) will be active only 5' per day) -
another solution would be to have several 3.7 cells in series to reach beyond 12V and then a step down regulator to get 12V, but several TP4056 can only charge as many 3.7 V in parallell : using the cells in series at the same time ==> shorcuts ! i did not find a low cost module equivalent to TP4056 to charge several such cells while they are working in series ...
so i'm back to 1) unless someone can suggest something else ...
-
-
If the solenoid valve only draws 0,3A it should not be a huge problem using the regulator. Keep in mind that there are also latching valves that only draw current to change state.
-
For the charger:
http://www.ebay.com/itm/MPPT-Solar-Controller-3S-12-6V-Lithium-Battery-Charging-18650-Charger-Module-zhn-/332313023330For the battery:
http://www.ebay.com/itm/1-3S-11-1V-25A-W-Balance-Li-ion-Lithium-18650-Battery-BMS-PCB-Protection-Board-/272761561101You need a balancer to charge Li-Ion batteries in series, hence the addon board.
It also protects against overcharging, over-discharging and overcurrent.You could also buy a battery pack with integrated balancer/protection:
http://www.ebay.com/itm/Portable-DC-12V-20000mAh-Li-ion-Super-Rechargeable-Battery-Pack-US-Plug-Lot-MU-/162662798231
