Tagged Questions

1
vote
1answer
45 views

Building a small D cell battery charger?

I am looking to buy/build my own D cell Nimh battery charger with the following requirements: -dual prong AC wall input -charges Nimh D Cell -is safe -contained within 1" x 1.7" x 2.2" enclosure As ...
0
votes
1answer
56 views

Charging 12V/4A battery

Can I charge a 12V/4Ah sealed rechargeable battery with a 13.5V/500mA charger? If so, how much time would I need to charge it to 100%? If not, how can I charge the battery?
0
votes
1answer
25 views

mobility scooter battery charger

I have a mobility scooter that I put a Raspberry Pi and Arduino on to make a robot. I left all the original electronics in place so I didn't have to buy a motor controller. I was able to charge the ...
-3
votes
1answer
86 views

How do I measure ripple current in a battery charger? [closed]

Minimizing ripple voltage is major factor to avoid failure of equipment such as digital axle counters. (Eldyne) How do I measure ripple voltage in a battery charger with a 230 VAC input and a 24 VDC ...
1
vote
1answer
54 views

Lithium Ion charging problems - power outages

Does any one know if general charge circuits for lithium ion batteries suffer from this problem: -Flat Battery put on to charge. -A power outage of long duration occurs (say 8 hours). -When power ...
0
votes
2answers
57 views

Why is this electro motor going slower?

From an old dust buster I've got this electro motor, the included battery pack and the charger: I ripped everything apart (the dust buster was broken) and the motor still works. After playing ...
0
votes
1answer
158 views

Charging phones via solar battery chargers

For a school project, I want to make a solar iPhone charger (specifically for the iPhone 4) and I've spent about a week looking up stuff all over the Internet, and I'm stuck for the hundredth time. ...
-4
votes
4answers
523 views

Can a phone charger be adapted to charge a laptop battery? [closed]

I've obtained a laptop that has no charger. Short of buying another charger online, can a phone charger be adapted to charge the laptop's battery, provided it's disconnected from the laptop (i.e., the ...
-3
votes
1answer
128 views

How high charging temperature causes damage to AA size NiMH cell

I used a portable thermometer and put on top of a battery charger. I notice that the temperature reach 39 degree Celsius and I can feel the warmth when I put my hand on top of the charger & the ...
1
vote
2answers
155 views

Why using short traces with the MCP73831 LiPo charger?

I'd like to use an MCP73831 to charge my lipoly battery. In section 6.2 I see they recommend short wires to the battery. I bought my battery with wires, 20 gauge and approximately 30cm long. The ...
3
votes
0answers
288 views

Parallel charge a serial pack, LiFePO4

I have an idea that I am trying to explore. I use 48V headway cell packs to power my various electric bicycle projects. Trying to balance charge a 16s pack can be a problem. I had the idea of using ...
0
votes
0answers
170 views

making USB charger but it isn't pushing enough power to the USB ports

I am in the military and trying to use BA-5590s the radio batteries as a power source but when plugged in it isn't pushing enough power. I am thinking of switching the resistors they were 12V chargers ...
5
votes
4answers
969 views

When using a Laptop, is it desirable to keep it charged from the Mains all the time?

While using laptop I usually plug in my Laptop charger (i.e., from Mains power). What is more effective - to keep Laptop plugged in at all times when possible, or some other approach (e.g., running ...
3
votes
1answer
495 views

USB to 3-cell Lipo charger?

I have a data-logger project that needs to run from a 3-cell Lithium Polymer battery. It has 5v and 3.3v regulators to provide regulated power to the system. I want to build the battery into the ...
3
votes
1answer
1k views

Smart charging circuit for NiMH battery pack

I want to build a solar powered charger for a niMh battery pack to run a microcontroller. What are the fundamentals of building a smart circuit that will not overcharge the battery and will also allow ...
2
votes
2answers
3k views

Building a USB charger for camping

I was looking into building a battery powered USB charger for camping. It occurred to me that car chargers are pre-built and run off 12 V. If I made a battery pack out of 8x 1.5 V batteries in series ...
4
votes
2answers
868 views

How to lay out a schematic for review? Please critique

So, because I haven't posted a schematic for review before, I have no idea how to do it. Apparently, my previous attempt was poor. I got some actionable feedback, but I'm looking for more! I would be ...
2
votes
1answer
612 views

19v Charger with 14.4v Battery: What exactly can I expect?

Long story short: I have to replace the charger AND battery on my ASUS U53F-BBL5 laptop due to a combination of lost original charger and Best Buy can't read a laptop's model number for the correct ...
3
votes
1answer
1k views

Can I recharge batteries with a normal AC to DC transformer? [duplicate]

Possible Duplicate: Charging 3 AAs in series My batteries charger is not working, but I have an AC to DC transformer that can output different voltages. If I connect two 1.5v ...
3
votes
2answers
591 views

Why do chargers heat up when operating?

From my experience all chargers for Li-Ion batteries notably heat up when charging the battery. Why does that happen? Is the charger acting as a not that efficient power supply or is there any ...
5
votes
1answer
215 views

How to power a widget, while the li-ion battery is charging?

I am in need of a way to charge a 3.7V li-ion cell (probably an 18650 type) from a 4.5V - 20V input. That's not a problem, there are plenty of (switching) battery chargers around with that kind of ...
1
vote
2answers
492 views

Charge 3x AAA from USB

I'm trying to charge 3 NiMH/NiCd AAA cells from USB. I've already got an atmega32u4, so I can use that to read battery voltage and stop when battery reaches 4.2V. I'm not sure about the capacity, but ...
2
votes
1answer
291 views

LiPo charger balance plug is kaput

Well, it seems that static electricity has fried my LiPo balance plug adapter. When I was plugging in my LiPo battery to it, which was plugged into my Thunder AC6 LiPo charger, a short wisp of smoke ...
0
votes
6answers
2k views

How to charge Laptop Li-ion Battery cells manualy?

I have received some Li-ion batteries which were originally used in Asus A2 Laptop battery original one and I would like to know if it is possible to charge each cells independently with some device ...
3
votes
1answer
286 views

How can I build a solar powered car charger?

I found 12 solar panels, but they are very thin and fragile. They put out approximately .5V under an incandescent bulb. What would be the best way to turn these 12 panels into a 12V car battery ...
3
votes
3answers
995 views

Mobile phone battery charger

I would like to know about the workings of mobile phone battery chargers. I know the basic principle, you take a transformer to bring it down to 9/6/3.7 volts then a bridge rectifier circuit and a ...