Questions regarding Li-ion batteries (Lithium-ion), including proper charging and usage.

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1answer
62 views

Charging Li-ion batteries in parallel

I wanted some opinion on my set up here, just to make sure I got the basics right. I have a Li-ion battery charging circuit based on the MCP73113. This is designed to be a single-cell battery ...
0
votes
2answers
26 views

USB li-ion charger with usb output

I would like to power my robot with li-ion batteries. The logic is 5V so I thought about something like this http://www.powerstream.com/n-charger.htm. This does exactly what I want - it is charged ...
0
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1answer
44 views

How can I regulate the voltage of a Li-ion battery with the least drop out voltage?

I have a one of these: descriptions: full charge voltage : 4.2V cut off discharge voltage : 2.75V capacity : 4000mAh size : 18650 And I want to get 3.3V from it. but the problem is I can't use ...
0
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1answer
56 views

Powering circuit and Arduino with single power source

I am trying to power an Arduino Uno as well as my circuit using Li-Ion batteries. They are 2 18650 Lithium Ion batteries (rated at 3.4 V each = 7.4 V total). I have this battery plugged into the Vin ...
0
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3answers
74 views

Double Li-ion charging circuit logic

I'm currently trying to adapt a single li-ion battery charger based on the TP4056 to work with charging more than one battery. The idea is to use a logic circuit that is controlled by the IC's "FULL" ...
2
votes
1answer
51 views

How to keep rarely-used Li-Ion batteries functional?

I have many gadgets around the house that I don't use often, recently I notice that a battery failed on an Mp3 player not used for a year. The battery now has a life of 1 minute from the original 5-7 ...
0
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1answer
44 views

Lengthen charge times with batteries

Would replacing a 3.7v 1000mAh lithium ion battery with a 3.7v 5000mAh lithium ion batter make my projects last longer between charges?
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2answers
100 views

Using Li-Ion battery while charging

I'm trying to design a custom intelligent electronic cigarette battery, but I'm more of a programming guy. I know basic electronics, but I need some help with the details. I've sketched up an outline ...
0
votes
1answer
87 views

Finding the right battery?

I have a 5v circuit that's running on a 3.7v 1000mAh battery. I got it changing just right and the circuit is running fine but it doesn't last as long as I want it too. So how can I find the right ...
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2answers
82 views

How do phones charge their battery at seemingly any rate with no issues? 500mA or 1A or 1.2A depending on the charger?

If most use some sort of li-ion battery, and those batteries like to be charged in CCCV format how can my phone charge just fine at 5V, 500mA or 5V, 1A or 5V, 1.2A just fine (actual current delivered, ...
1
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4answers
109 views

Will voltage or current determine a diode drop for this battery charging circuit?

I am using a li-ion battery charger IC that regulates an output to 4.2V. I have a schottky diode in series with the output that then connects to the battery. How do I determine the voltage drop? If ...
-3
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1answer
48 views

Is this Li-Ion safe? [closed]

"TIANPENG li-ion 1300mAh 7.4V" is what the text on the battery is. Do you need internals of the charger? The battery 'case' (or whatever is holding packs of cells together) is cracked in some places, ...
1
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1answer
472 views

How To Blink LED's with MOSFET in response to Music?

trying to blink LED's by music. i've done this circuit no problem: Now wish to accomplish the same thing using an N-channel Mosfet. I tried this circuit, and got no blinks. Also no success with ...
0
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2answers
72 views

Alternatives to relay/contactors in DC circuits

I wanted to switch a 60Vdc line to ON/OFF using a 60Vdc controlling signal for some kind of a feedback system (yes both are 60Vdc). Presently I have two options visible: Solid State 60Vdc input ...
0
votes
1answer
56 views

Getting 12V out of 60V battery bank

I have a 60V battery bank with 16 Li-ion cells in series. I was wondering if I could get 12V output by connecting a wire across 3 or 4 cells in series and using it to control the 12V dc fan of the ...
0
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1answer
52 views

Is there any way to control a 12Vdc relay using 60Vdc line

I have a 60V li-ion battery back with PCM board attached to it for protection. According to the PCM datasheet, under fault condition the PCM cuts off the load and thus isolates the battery bank. The ...
2
votes
1answer
121 views

Temporary, high-power energy storage

I'm currently building a small, portable human-powered charger for supplying a 1W led. I salvaged a dynamo core from a torch, but I'm unable to use other components inside since the torch is only ...
3
votes
1answer
56 views

Charge a Lipo with only Constant-Current Stage?

I'm following this standard algorithm: http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries Algorithm for charging LI-PO batteries? but am wondering if I can get ~80% of the ...
2
votes
2answers
209 views

Is it ok to use an old phone as an universal battery charger?

We know that a charger is just an adapter that supplies a constant voltage (5 volts usually). The actual charging circuit is in the phone itself. With a bit of soldering and wiring, can I use my old ...
2
votes
2answers
126 views

Can Lithium Ion Batteries be used to generate heat for a RC Hot Air Balloon? Any particular heat-generating device?

First the background: OK - this is a personal project that I've always been interested in trying but never got around to it - a remote controlled hot air balloon. Sadly I am not technically-inclined ...
1
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2answers
115 views

Confusion regarding the design of Lithium Ion PCB

From this site and many others, it seems to be universally recommended that a lithium ion battery not be discharged lower than 3.0 volts. Most actually recommend to stop discharging at around 3.3 ...
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2answers
198 views

Simplest possible circuit for charging a li-ion cell

I want to create an ad-hoc single cell li-ion charger. I have a buck step-down that can supply 4.2 volts. If I connect a 1 ohm resistor in series with the lithium cell, the current should go down to 0 ...
1
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1answer
443 views

Calculating battery percentage using an Arduino

I'm doing a little project using a Lipoly charger and a 2500mAh 3.7V battery, both from Adafruit. I'm trying to display the percentage left on the battery. For that I'm using this little sketch : ...
0
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3answers
127 views

Replacing li-ion cells in handheld drill battery [closed]

I am considering to replace the 18650 battery cells in a 3S1P 11.1V cordless drill battery pack rated at 1300mAh, with three 2200mAh cells from a salvaged laptop battery pack. One of the four cells ...
0
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1answer
76 views

Can you use an iPad battery with an Arduino?

I'm looking to power an Arduino based project with a sufficiently large lithium battery so it can run for hopefully a week or more of constant use (ultrasonic based traffic counter). For large ...
0
votes
2answers
91 views

Can a 9v battery be substituted with an array of LiIon 3.7v?

I use some audio devices (mixers and effect boxes) that literally drains out my 9v cells (specially the rechargeable). I'm thinking on doing arrays of LiIon batteries (rated at 3.7v-4000mAh each), ...
6
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4answers
958 views

Why is balancing used for lithium batteries only?

I have never heard of a lead acid battery having any electronics to balance it's cells, or even any manual way to balance them. But I think all lithium batteries have, or at least lithium batteries ...
1
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1answer
152 views

Charging 7.4V Li-Ion battery

I'm making a battery out of two 3.75V Li-Ion cells to go into a speaker system that powers an amplifier. I was wondering on the PCM, how many volts would be max to charge these cells? The cells I have ...
0
votes
1answer
100 views

Measuring smartphone's battery State-of-Charge during charging

I'm designing a mobile device that uses a Li-Ion battery. It is required to indicate to the user the State-of-Charge of the battery, similar to how it's done in smartphones. At first I considered ...
1
vote
2answers
298 views

Charging 2 Li-Ion Batteries via a single charger

I'm currently building a portable USB charger. It uses 2 Li-ion batteries in series connected to a USB port via a 5V regulated buck converter. While a single Li-ion battery would suffice for most ...
4
votes
2answers
488 views

Is charging an empty Li-Ion cell to 50% more or less efficient than charging it from 50% to 100%?

Many devices that are powered by a Li-Ion battery can be recharged over 5V DC supplied by a USB connection. Is the 5V voltage internally converted by the charging logic to something lower, and is ...
1
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0answers
107 views

Measuring a 2 cell 18650 battery from ATMega328P

I'm using an ATMega 328P (which will be running arduino code) as part of a project (a bicycle lighting system). It runs off of 2 Li-Ion cells, which both are step-up-regulated to 12V for the lighting, ...
1
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2answers
115 views

How to efficiently heat a lithium-ion battery so that it can be charged in sub-zero environment?

A common knowledge and practice on lithium-ion batteries is that they significantly loose the capacity and cannot be charged when their temperature drops below 0 deg of Celsius due to increased ...
0
votes
3answers
178 views

Using Lithium-ion batteries in series

I am trying to build a robot with the minimal components and an Arduino UNO. It needs 7V to 12V input or 5V. So I thought as a replacement of using 6AA, I'd use 2 li-ion of 3.7V in series. My ...
3
votes
1answer
95 views

What affect does charger wattage have on lifetime of LiIon batteries?

This questiuon is generic to LiIon and LiPo batteries but a Mac is used as an example. A Mac 'laptop' is provided with a 85 Watt charger. It is possible to charge it with 45 Watt charger that was ...
2
votes
1answer
536 views

Maximum *charging* voltage for Li-Ion battery

I'm implementing a CC-CV algorithm for charging a li-ion battery. I'm confused what is the maximum allowed charging voltage during CC (constant current) phase. All application notes and datasheets, ...
2
votes
1answer
51 views

Li polymer cells in parallel

I am using two 3.7V LiPo cells in series to power a device. The output of battery is converted to 12V using a dc-dc converter. I want to increase the capacity so that the device can run longer. Is it ...
0
votes
1answer
150 views

What does 1.0 It current mean?

A datasheet of Li-Ion battery states "The current should be maintained at 1.0 It or less". What kind of unit is It?
1
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2answers
103 views

Combined chip with LDO and Buck, what use?

I am searching for a Li-polymer 1A charger with a 3V regulated output. I have found Linear LTC355x serie but can't, after reading many "LDO vs Switching" debates, understand the use of both on the ...
1
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1answer
231 views

Charging lithium batteries with solar panels

Let's say I have a battery pack made from 3 lithium-ion cells connected in a series (making a battery with around 12 volts). That battery pack has a PCB with balancing function and also protects the ...
2
votes
1answer
140 views

Can I use this Anker Astro 3e to power my arduino through the usb?

http://www.amazon.com/gp/product/B009USAJCC/ref=oh_details_o00_s00_i01?ie=UTF8&psc=1 Will there be any electrical problems? I'm building a arduino controlled car (with a chassis like this: ...
2
votes
1answer
154 views

What battery has more capacity: Lithium Polymer or Lithium-ion battery?

In my project I need a battery with a cylinder of 10mm diameter and 35mm high. I thought only Lithium Polymer technology can create battery for this size. Now I discovery Lithium-ion can have the same ...
-1
votes
1answer
285 views

How to hack a battery powered device to use 1 Li-ion cell instead of 2 NiMH cells?

I want to hack a cordless computer mouse, so it can be used with 1 lithium ion cell (standard cobalt cathode to be extra precise) instead of the intended 2 nickel metal hydride cells. The main reason ...
3
votes
2answers
1k views

Charging and Using a Li-Po battery simultaneously

My system requires a power which is supplied by a Li-Po. however, I need to keep this Li-Po charging at all time so it won't die. Is it possible to connect the Li-Po to my system and also have it ...
0
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1answer
197 views

balance charging current for batteries connected in series

I've been using this simple Li-Ion charger for quite a while. It consists of 4x 18650 Panasonic NCR Li-Ion "unprotected" batteries (3.1Ah), connected in series (2+2). Charging was going well with cell ...
2
votes
1answer
290 views

Can someone clarify how to charge a battery without an off-the-shelf battery charger?

I am a college sophomore studying EE, I am currently working on making a simple battery charger circuit for an integrated device. The device has 3 Li-Ion batteries in series for my motors, and a ...
0
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1answer
79 views

Charge controller for Li-ion or Li-Polymer battery

I am trying to work out the good charger for Mobile phones, which can serve as good performer for various smart phones out there in market these days & mostly using Li-ion battery. Charging has 4 ...
5
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3answers
2k views

What is the meaning of a battery's “cycle life?”

I started to read about batteries, I am interested in lithium batteries, I found a description regarding the stability and capacity/weight, but I read some unclear descriptions like "cycle." What ...
1
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0answers
135 views

Does a crude Li-ion 18650 battery have internal thermal (mechanic?) protection?

For clarification: crude means "it does not have any protection circuit attached". Short history long: I extracted 6 18650 (Sanyo) batteries from an Acer battery pack. They had more than 3V each and ...
2
votes
1answer
82 views

When rechargable battery age, what quality decreases?

When a rechargeable (li ion) battery has many cycles and begins to wear down, what quality actually diminishes? I know it can hold less charge, but is this evident in the potential difference it can ...