# Increasing AMPERAGE of a DC Circuit

Discussion in 'General Electronics Chat' started by Soomro, Jan 27, 2015.

1. ### Soomro Thread Starter New Member

Nov 20, 2012
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I am a hobbyist and been working on a solar panel project recently; I've got a panel which produces 10v at 400 mA at bright sunny day whereas in dim light, it’s around 160 mA. I am trying to increase amperes up to 2 Amps for charging batteries for a remote car. I tried making a boost converter using NE555, I was able to increase voltage up to 70 volts however amps remained same or lower in most cases (without load).

I want to keep this handy without purchasing another panel; is there anything else that I can do to increase amps of my circuit. I will store this energy in 1200 mAH battery if battery level goes lower than specific level.

2. ### Alec_t AAC Fanatic!

Sep 17, 2013
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You can't get power from nowhere, and the panel can only provide so much. Power (Watts) = Volts times Amps. The higher the current the lower the volts. A DC-DC converter may enable you to trade current for volts. What voltage is the battery?

3. ### MrChips Moderator

Oct 2, 2009
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The power generated is fixed for a given solar output (if we ignore MPPT for the moment).

If you want to increase current you will decrease voltage. Your solution is to get a bigger solar panel.

4. ### Soomro Thread Starter New Member

Nov 20, 2012
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Guys, thanks for speedy answers. I can add more panels however I am doing this research to have grip over my electronic understandings; I got a 4.6v battery at 1200 mA and I want to charge it with this panel and then utilize it with RC toy car but as it's 1200 mA, I don't think connecting panel directly using a diode will charge it. Right? And adding more panels would make it odd, where would I fix a big panel in a toy car?

I was thinking if some form of circuits exist where I can get voltage from panel and store it in big capacitors and then release it slow and steady with higher amperage. @MrChips, how can I decrease voltage and increase amperage, do I have to use voltage divider for that or use 7805 regulator? And how much can I get through it.

5. ### Soomro Thread Starter New Member

Nov 20, 2012
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Let's just assume and go to basics that a voltage is pressure of water and current is actual water following through a channel. Correct me if I am wrong? If I am correct then we can store this water (current) somewhere and then utilize it for some other purpose. I need to do something like that, I don't know if it is possible or not but can there be something like having 10v at 400mA, storing it for few seconds and releasing it with 5v at 2amps?

6. ### MrChips Moderator

Oct 2, 2009
12,657
3,461

Batteries have a capacity rating, such as 6V/1200mAh, not simply a current rating (note the h in the units).

So how long can a 1200mAh battery supply 2A (assuming that it is capable of doing so)?

duration = charge/current = 1.2Ah/2A =0.6 h = 36 minutes

Now suppose your charger can supply 400mA.
How long will it take to fully charge a 1200mAh battery (assuming 100% efficiency)?

duration = charge/current = 1200mAh/400mA = 3 hours

The best you can do is place a diode between the solar panel and the battery. Then hope that the voltage output from the solar panel exceeds the battery voltage by at least 1V and let the car sit in the sun for 3 hours for every half-hour of run time (using the numbers that you have provided).

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7. ### foolios Active Member

Feb 4, 2009
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Are you trying to speed up how fast the toy car battery is charging, thus reducing the amount of time it takes to charge it; by upping the amps?
How many amps maximum can a 1200mah battery handle of in-rushing current?

It sounds like you want a way to store power. Do you have a second set of batteries for swapping? Not sure what you are trying to accomplish. Is this just about how fast you can recharge a rechargeable battery?
I guess one way to increase voltage/amps into the battery; not sure which(amps or voltage) since you mentioned increasing both; would be to add another panel in series for the voltage increase or a battery in parallel for the amperage increase; or a mix if you want both, but have to add more panels still if its both that's desired.

8. ### Evil Lurker Member

Aug 25, 2011
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You can get more volts out of a boost converter, but the only way you are going to get more amps is by installing additional solar panels.

9. ### wmodavis Well-Known Member

Oct 23, 2010
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Make sure the PV panel surface is directly facing the sun at all times.

10. ### Soomro Thread Starter New Member

Nov 20, 2012
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Quite helpful discussion, thanks everyone especially @MrChips for the calculations. I think I will have to compromise or add more panels or batteries for additional power.