Lithium Polymer batteries
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0answers
64 views
How can I use arduino to control 4 motors speed and direction?
I consider this question different from others because of the variety of things I need this setup to be able to do.
Description:
I want to build a minimalistic motor controller capable of controlling ...
2
votes
1answer
53 views
Charge LiPo battery with solar panel
I've a solar panel of 5.5 V and 100 mA. Could I use it to charge LiPo batteries using the MAX1555?
Of couse that the voltage will drop due to the the Schottky diode.
6
votes
3answers
280 views
NiMh or LiPo batteries for unattended charging/usage
I'm in the planning stage of a summer project: A WiFi controlled robot for remotely monitoring a shore home. The robot will consist of a 4-wheel platform (4 motors, 1 A stall current each, 7 V), ...
2
votes
2answers
73 views
DC/DC Booster to 5v 500ma?
I'm trying to find a circuit capable of boosting a normal alkaline battery or maybe a li-po to 5V/500mA. I want a through hole IC to try it on the breadboard.
Vin could be 2.5V (or lower) and maximum ...
2
votes
3answers
155 views
Low current battery monitoring
I want to run a micro-controller from a 1S lipo through a 3V linear regulator. I need to measure the battery voltage however. The problem with using a voltage divider is that it would drain the ...
0
votes
2answers
140 views
Calculating “useable amps”
We use a 1650 mAh capacity LiPo battery.
It has a 2.5volt undercurrent protection cutoff set.
Our device uses a CONSTANT 5mA of draw UNTIL the battery
drops down to 3.2V, at which time the system ...
1
vote
0answers
111 views
How to charge LiPo battery using a wind generator?
For a home robotics project I want to fly a kite using a computer. For this to happen I need an electro motor up in the air (attached to the kite) which obviously needs a battery up there as well. ...
4
votes
1answer
69 views
Would it harm a LiPo to charge it in several periods?
I have a 3.7V 5000mAh Lithium-Polymer battery cell, which I'm charging with the MCP73831, using the typical application circuit on page 1:
I have \$R_{prog}=2\text{K}\$ and \$V_{in}=6.0\text{V}\$. ...
1
vote
1answer
77 views
LiPo discharge circuit doesn't work
A friend of mine gave me this circuit to discharge a 3V7, 5000mAh single-cell LiPoly accu:
simulate this circuit – Schematic created using CircuitLab
The zener is to make sure that the ...
4
votes
5answers
142 views
Choosing the type of battery for a project
I am working on a machine which consists of 10 servos, and one microcontroller. The servos need to be on pretty much all the time for about 8 minutes. I am planning on using the ATmega16 to provide ...
-1
votes
1answer
740 views
Battery powered portable wall outlet?
For a college competition we aren't given any wall outlets to power our devices. We are purchasing (we don't have it yet) the wireless camera kit in the following link and we need to rig up a portable ...
4
votes
3answers
254 views
A separate MCU to cutoff LiPo on low voltage?
I'm designing a project that is going to work on a flying quadcopter. It features an ATmega328P MCU in the main 5V circuit, and is powered by a small (<500 mAh) 1-cell LiPo battery. I want to ...
1
vote
1answer
147 views
Obtaining +- 1.5V, +- 20V, and 3V from single LiPo [closed]
I want to use a 3.7 volt LiPo to power a portable device. What's the best (efficient and small) way to get ± 1.5V, ± 20V, and 3V from a single cell LiPo?
Here are some specs about the ...
4
votes
3answers
129 views
Can I draw power for a component while this charger is charging the battery?
So I am working on a design for battery-heated wrist warmers. My mother has Reynauld's and arthritis, and as winter approaches it gets much worse.
My basic design is that I will take a form-fitting ...
1
vote
1answer
238 views
Lipo battery monitor for 1s-6s packs
I want to be able to output lipo battery voltage to a display the remaining juice in the battery much like a fuel gauge. It has to work for 1s to 6s batteries and it would be ideal to work using an ...
0
votes
0answers
101 views
Atmel UC3L/SAM4L + 2.8V peripherals li-pol charger and power rails (PMU/PMIC ?)
I am designing a very tiny low-power Atmel UC3L (or SAM4L) project and I need the smallest solution for safe Li-Pol charging and to provide 2.8V and 1.8V power rails.
I found some LTC parts with dual ...
2
votes
2answers
204 views
Slow charging a li-po battery
I am working on a project that has a micro-controller that needs to keep track of time over long periods, the project will be powered of mains power for the vast majority of the operation time, but I ...
3
votes
3answers
1k views
Under Voltage Protection for LiPo Battery
I have a 3Cell LiPo battery which I am going to use with an RC Car, and I want to design a circuit to protect the battery cells from going under ~3.3v each. So what do you think of this design?
As ...
6
votes
1answer
442 views
LiPo vs. NiMH for kid's toy
I've been researching here and on google regarding potential battery technologies for a toy that I want to make for my kids. I was hoping to get others' perspectives on this, keeping in mind that ...
7
votes
1answer
160 views
Before storage why should a Lithium Polymer battery be charged up to only 40-60%
While storing a Lithium Polymer battery cell or a device with a Lithium Polymer battery why should we make sure to discharge the battery to 40-60% (and only then put it to storage)?
What happens if ...
3
votes
1answer
494 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 ...
2
votes
1answer
376 views
Li-Po USB Charger with PIC, voltage is not falling to 0V
I am designing a single cell Li-Po charger with a PIC. I have this:
I drive the transistors from a 12F PIC microcontroller. As you can see in the square wave on the top of the oscilloscope the ...
2
votes
3answers
783 views
Lithium Ion charging schematic
I am using the MCP73831 along with a Lithium Ion battery to supply an Arduino Mini project. Is it safe to supply my project directly on the battery? Or should I use a transistor to protect the project ...
4
votes
2answers
265 views
Circuit safety -> Preventing smoke through accidental connection of battery voltages
I'm building a circuit whereby users are able to connect their battery to the pcb which will then be sampled by a micrcontroller. Voltage divider circuitry is all good so please don't focus you ...
4
votes
2answers
1k views
How to charge Polymer Lithium Ion Battery that comes with the Lilypad Development Board
There is a Lithium Polymer Ion Battery that comes with the Lilypad Development Board from Sparfun. Does anyone know if the battery charges if we plug in the battery to the Lilypad Arduino and connect ...
3
votes
1answer
660 views
Charging a 12.6V 3SLiPo from 5V USB (Or similar) voltage?
So, I understand that a 3Cell LiPo battery can output 12.6V when fully charged and that the cells must remain balanced to guard against Fire/Explosions/and general bad stuff happening.
However, each ...
0
votes
1answer
151 views
MCP73834 disintegrates after a couple of hours
For my first attempt at Li-Po charging I chose the MCP73834-FCI/UN for availability, it has an output current of 1A. I set it up the example circuit in the datasheet and used an 6Ah battery to test ...
3
votes
1answer
275 views
BLDC Regenrative ESC and LiPo
I am currently working on a project where I want to implement a Brushless dc motor (like the Turnigy C2226 - 1800kv) to run in-hub of an RC car. I need this entire project to be as lightweight as ...
2
votes
4answers
874 views
How to power a GSM Modem from a Li-Po battery?
I want to integrate an AirPrime SL6087 GSM modem into a design, this is my first try at working with a GSM module. The datasheet states that the modem draws 2A for 1mS every 4mS (max) at 3.6V, the ...
0
votes
2answers
1k views
Adding voltage cutoff to a circuit? 3s li-po [duplicate]
Possible Duplicate:
Adding voltage cutoff to a circuit?
Adding voltage cutoff to a circuit?
I'm powering a project with a 3-cell 11.1V LiPo battery. What circuit do I add to make the unit ...
2
votes
1answer
451 views
Battery charging questions Parallel charging and battery balancing of LiPos
I'm having a long discussion on an RC board regarding LiPo parallel charging.
The basic crux is that my understanding of how charging works is something like this:
Charger Line voltage of x(8.4v in ...
1
vote
1answer
422 views
LiPo series charging
I have a 3 cell lipo connected in series and I want to charge them without removing them from circuit.
I only have single cell chargers so I can only charge one at a time or charge them in parallel ...
8
votes
2answers
1k views
“Breaking-in” lithium polymer batteries:Is there any research on that?
Well I just got new batteries for my RC glider and I'm thinking about what to do with its battery.
For those who aren't in the RC hobby the story goes something like this:
New kid buys a battery and ...
2
votes
1answer
317 views
POE Battery Survey Toolkit
I want to try my hand at producing a POE battery power supply for use with an access point [AP] for site surveying purposes.
My solution is an 11.1v LiPo 3s pack and charger fro a remote control car ...
5
votes
4answers
3k views
Parallel charging of lipo batteries, maximum voltage difference?
There are numerous products that enable lipo batteries to be charged in parallel.
Most sources are clear on voltage and capacity requirements, which follow pretty directly from basic circuit ...
3
votes
3answers
2k views
Adding voltage cutoff to a circuit?
I'm powering a project with a 2-cell 7.4V LiPo battery. What circuit do I add to make the unit stop drawing power when the voltage from the battery drops below 6.4V? The goal is to protect the LiPo ...
0
votes
1answer
477 views
Reading a Li-po battery's remaining charge
I want to read the remaining charge on a Li-po battery in a device I'm making but I'm confused as to exactly how to get an accurate reading.
I know that the voltages of the battery are different ...
2
votes
1answer
217 views
LiPoly batteries and 3.6V digital ICs
Li-Poly battery voltage changes a lot while discharging — from 4.2V to 2.7V. Most modern digital ICs (I'm currently thinking of Cortex-M3 microcontroller and an RF module) require input voltage levels ...
1
vote
1answer
324 views
Algorithm for balancing LI-PO batteries?
The answers to this question provide a good overview of how a single lipo cell is charged:
Algorithm for charging LI-PO batteries?
Most chargers that handle lipo packs have a balance mode that ...
4
votes
4answers
975 views
Algorithm for charging LI-PO batteries?
What is the algorithm used in charging lipo batteries?
From watching my charger, I see that the amperage is close to the maximum specified (i.e. what I keyed in) at the beginning and gets smaller as ...
3
votes
2answers
998 views
Circuit for testing LiPo batteries?
I have some lipo batteries I'd like to test. Ideally it would do the following:
how much time does it take to discharge to minimum allowed voltage?
how flat is the discharge curve?
how many mAh ...
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 ...
6
votes
5answers
455 views
Need help with LiPO batteries
I am planning on a 1 cubic inch robot as my next project in robotics and the biggest challenge I am facing is on the battery. Lithium polymer seems to be the best option in terms of weight and the ...
