|August 27, 2014|
Universal lithium ion battery pack
|This powerful little battery pack is very flexible, it can act as a 5 volt battery or a 19 volt battery with 6 steps in between. Outputs at 5V, 6V, 7.5V, 9V, 12V, 14V, 16V and 19V. It can also be charged with voltages as low as 9 volts and as high as 24VDC.|
This battery pack consists of a 44 watt hour lithium ion battery assembly and three DC/DC converters. The first DC converter allows the pack to be charged with a wide range of voltage inputs. The second allows the pack to deliver a user selectable voltage to run equipment requiring 5volts to 19+volts. The third DC converter supplies a steady 5 volts to a USB port for charging cell phones, Ipods, and other USB charged equipment. All this is built into the sleek black battery case.
For example, when used with your cell-phone car charger attached the PST-MP3500 can run a typical cell phone for 15 times longer than the battery in the phone, or charge the phone 10-15 times. You can double the battery time for a laptop computer, or use a digital camera up to 20 times as long as when using disposable AA alkalines.
Special Features :
Typical run time calculations
Voltage versus time discharge curves.
You can see that unlike plain batteries this pack delivers regulated voltage until the pack runs out of juice. This is very helpful for instruments, cameras, thermal cameras, lights, and other applications that work best with regulated power. For comparison, most laptop batteries use 14.4 volts and 2.2 AH, so this can run a laptop longer than the built-in battery.
Many laptops can be run at lower voltage than the manufacturer's power pack would indicate, they just can't charge the battery at lower voltages. In this case it is a good idea to run the battery pack at 12 to 14 volts so no power is wasted charging the laptop's internal battery. However, you can't always use this trick, my ACER won't run at all unless I give it the full rated voltage.
Click here to download a quick-start PDF graphic manual that shows how to use these external battery packs.
Questions and Answers
Q: Is it legal to take these spare batteries on airplanes?
A: The PST-MP3500 has about 3.2 grams of equivalent lithium, and the combination of the PST-MP3500 and PST-MP3460 contain about 6.4 grams of equivalent lithium, so they are OK to take in carry-on luggage. See the government web page http://safetravel.dot.gov/whats_new_batteries.html for more details.
Q: I have a 60 watt laptop, will this 50 watt battery pack work with it?
A: Yes, the 60 watts is the maximum that the computer can use, including charging the internal battery. It is recommended that the PST-MP3500 be used when the laptop's internal battery is full or removed. Some computers will also run fine on lower voltage (12V, 14, or 16V) which will prevent the internal battery from being charged, if you don't waste energy charging the internal battery you will get you even more run time from the external battery pack. In addition the PST-MP3500 can supply up to 60 watts when the laptop needs peak power.
Q: The AC charger that is included, is it a peak charger? So that it switches off the charging process when the battery is fully charged?
A: The charging circuit is actually built into the battery case. So the charger that comes with it is just a power supply. In fact any voltage between 9VDC and 24VDC can be used to charge it. The internal charger is a smart charger, it will not overcharge the battery. In fact when I am in China I leave the battery connected to the computer and run the "charger" into the battery. That way I only have to bring one power supply with me.
December 2006. I have been using one of these packs since July of 2006, first on a trip to China and then on several smaller trips and also to create the curves shown above. It was very nice to be able to run my 60 watt Acer laptop as long as I could stand to work on the bus and the plane rides. You can also see the impressive voltage regulation and runtime from the curves.
I have also been impressed that it will recharge from voltage sources as low as 5 volts, I have recharged mine at 5 volts, 9 volts, 12-14 volts (car cigarette lighter), at 14, at 16, 19, and even 24 volts. I am sure that it will charge at any voltage above 5V and less than 24V. I have a little solar charger that I would like to try, but my office window faces north toward the mountains and I don't get much direct sun. However, in practical terms, the source current is 1 amp no matter what the input voltage is, after covering the chargers' DC converter overhead the charge rate at 5 volt input is very very low, so in practical terms 9 volts is the lowest you would want to use.
Recently I arrived in the parking lot for my meeting just as my cell phone "dead battery" beep started up. I was waiting for an important call and didn't want to leave my phone in the car for charging. So I just plugged my phone's USB charger cable into the MP3500's USB port and put the combination in my briefcase. When the phone rang in my briefcase it was charged enough to handle several calls and I got to show off my fun battery pack at the same time.
I wrote a WordPerfect macro to time how long it took for the computer to shut down due to running low on battery power. Then I ran my Acer a couple of ways to measure how much more time the MP3500 gives me.
Harry M: I would like to say that this is the BEST UPS appliance I've come across with and I'm very pleased with the product itself. I'm planning to buy more in the near future for other experiments.