Tagged Questions

Lithium batteries are disposable/non-rechargeable batteries, often found in button/coin-cell form and sometimes in cylindrical cell form. Lithium batteries are used in portable consumer electronic devices, including watches, cameras, calculators, thermometers, etc.

learn more… | top users | synonyms

1
vote
1answer
47 views

Why are the charge and discharge rate of Lihium Polymer Batteries different?

I have a 3S 1.3MAH Lithium Polymer battery with a 25C discharge rate, and a 5C charge rate.From what i know, the discharge rate is the rate at which the battery can be safely ischarged( i.e how many ...
1
vote
2answers
59 views

Safe Lithium Battery Management

I'm building a device that needs to run from Lithium batteries. I am well aware they need to be charged/dis-charged properly to avoid damage and explosions. To my knowledge a charging system has ...
0
votes
2answers
65 views

Can I swap any two lithium cells on an MP3 player / camera, etc?

Lithium batteries commonly have +/- and temp monitor connections. I'm pretty sure I can swap a 290 mAh MP3 battery with a 1400 mAh battery, it will charge very slowly. Can I swap the temp sensor ...
1
vote
1answer
38 views

Difference between Lithium Polymer batteries of varying capacity and cell amount

I was looking to purchase a LiPo batteries online for a side project. Upon shopping around, and reading up on LiPo batteries, I have a fair understanding on what the numbers/letters on the battery ...
1
vote
0answers
38 views

Li-SoCl2 battery state of charge

I'm developing a data logger powered by Li-SoCl2 (http://www.100y.com.tw/pdf_file/02-SAFT-LS33600.pdf) battery and I have no idea on how to overcome the problem of estimating the residual charge of ...
1
vote
2answers
47 views

nexus 7 battery repurposing [closed]

I have just broken my nexus 7 and I was about to salvage the battery. I was thinking of using it maybe to power my raspi or arduino. My main question is how do I charge it? I was thinking of cutting ...
1
vote
2answers
61 views

How to handle / dispose of spent lithium primary cells [closed]

Disclaimer: This is a material safety question and not electrical. But it is electrical engineers who generally decide which type of battery to use when designing a system and other electrical ...
1
vote
1answer
70 views

What Lithium chemistry in phones' (now) 3.8V batteries?

I'm specifically looking for the discharge tolerances...can communicate with the charge controller on the phone and want to increase the discharge depth from 3.5V to say 3.1-3V for longer battery ...
-1
votes
1answer
99 views

What do B+ and C+ mean on the wires of a Lifepo4 battery pack?

I bought this Lifepo4 battery pack. It came with its own charger. The seller told me the charger can be connected directly to the battery. There are 4 cables coming out of the battery: C+, C-, B+ and ...
1
vote
2answers
148 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 ...
-1
votes
1answer
174 views

Why do batteries leak/explode, and how can I prevent it? [closed]

I've been the owner of many-a-battery which blew up, particularly inside of flashlights. I've recently purchased a fairly-decent-quality flashlight, and I'd greatly like to prevent the battery from ...
0
votes
1answer
450 views

How to charge double cell lipo battery with single cell charger?

My setup is simple: I have this bluetooth module with a built in single-cell Lithium ion/polymer battery charger. I have this double cell LiPo battery and I also have an arduino nano that I will have ...
0
votes
0answers
83 views

Discharge limit on a 12V 9800mAh Lithium-ion Battery

I am running a 12V solar system that powers a 5050 LED light bar of 7.4W. Powered by a 25W mono PV and has a total 12V storage of: 1x 6800mAh 1x 9800mAh (Lithium-ion batteries in series) The ...
1
vote
2answers
80 views

Need to charge a lithium power pack from USB

I need to charge a small lithium power pack from a device that was originally charged using a 5v USB connection. The connector on the device is damaged so I need to charge the power pack directly. ...
1
vote
1answer
194 views

Upgrade a cordless screwdriver (16.8 V) to Li-Poly [closed]

I'd like to upgrade my cordless screwdriver/drill to use lithium polymer batteries. Problem is, the screwdriver uses 16.8 V at the moment (14 NiMh 1.2 V cells). So, using lithium polymer batteries ...
-5
votes
2answers
356 views

Which are least likely to leak? DealExtreme “CR” coin cells, dollar-store “CR” cells, name-brand “CR” cells, or name-brand “BR” cells? [closed]

Please imagine this scenario. You own three watches. A $5 watch, a $20 watch, and a $30 watch. Each one uses a different size of lithium button-cell battery. You know that dead cells tend to leak ...
2
votes
2answers
5k views

Will a device charger with higher current output necessarily charge an electronic device faster?

Charger specs Charger type : USB Charger Voltage : 5V Amp : 2 Amp Freq : 60 Hz Battery specs Type : Li-ion Power : 7.4 Wh Current : 2 Ah Discharge Voltage : 3.7 V Charging limit voltage : ...
0
votes
2answers
1k views

How should I connect multiple Lithium Polymer battery packs in parallel?

I have an application for which I need a relatively high amount of current @5V. I was thinking of connecting four external USB battery packs like these in parallel, as they output a nice regulated 5V ...
1
vote
3answers
112 views

Is it safe to have 4V continuously supplied to a lithium battery?

I have a compact digital photo camera that will be on for very long periods(for a time-lapse video). It is powered by a Lithium-Ion 3,7V, 720mAh battery I want to supply 4V to the battery terminals, ...
3
votes
1answer
132 views

What are the possible causes of sudden extremely high internal resistances in Lithium batteries?

Not a duplicate, just to separated a good question from Does a crude Li-ion 18650 battery have internal thermal (mechanic?) protection? Short history long: I extracted 6 18650 (Sanyo) batteries from ...
1
vote
0answers
160 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
0answers
103 views

Isolation between cells for battery charging & testing

I want to charge Lipo battery packs and possibly other chemistries too. Six cell packs for starters. But hope to handle more and less. Perhaps a lot more cells. For electric vehicles, skateboards, ...
6
votes
1answer
383 views

Boosting a Lithium Coin Cell

I made a board recently and just started checking it out yesterday. I used a typical lithium coin cell and a boost converter (Microchip MCP1640). With a battery plugged in I get no voltage out of the ...
1
vote
1answer
120 views

In circuit 2S Lithium Charging

I'm designing a board with a micro that controls a hobby servo. The circuit is usually powered from 12VDC but may be disconnected at any point, thus we have 2 lithium cells in series providing ~7.4V ...
0
votes
0answers
95 views

Recycling a notebook battery pack

I've got an old battery pack ( from DELL ) to dismiss because batteries are gone. The battery contain an SMD board that I think being the charger module, and I would like to ask if that module can be ...
2
votes
1answer
7k views

How to Calculate Theoretical Capacity and Energy Density of Li Ion Battery

Specifically if the cathode and anode are known materials how do you calculate the theoretical capacity and energy density of the full cell? For example if you have a Lithium Iron Phosphate cathode ...
0
votes
1answer
651 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. ...
2
votes
1answer
302 views

From Li-Ion to Li-Po battery: design a new battery pack for old mobile phone

I have an old working mobile phone. The battery, a compatible 3.6V 500mAh Li-Ion is almost dead (the original one was 800mAh). Is it possible replace the battery pack with a 1200mAh or so Li-Po ...
0
votes
3answers
100 views

Large battery, small component. Issues? [duplicate]

I have a basic question which I wanted to run by some better informed people than me. I'm planning on building a very simple circuit which takes a 12v feed from a broadcast camera and uses it to ...
4
votes
1answer
714 views

Lithium-ion rechargeable battery, shelf life

For Lithium-ion rechargeable batteries, that have never been charged, or been charged like 2-3 times at most, some 2-3 years back, and having since-then been in packaged condition, what should I ...
1
vote
1answer
41 views

What are some good methods for adding charging control/signaling for a docking wireless system with a rechargeable battery?

I'm working on a device that will dock to charge very similarly to a cordless phone. The dock outputs 5V DC, which is already very low risk, but I would prefer to add a control pin that turns on the ...
0
votes
1answer
513 views

Li-Po shield for Arduino with in-line recharging, soft-off and voltage protection?

I'm looking for a shield for my Arduino (or a breakout board that I can adapt for the purpose). It should have these abilities: JST connector for my single-cell battery. Over- and Under-current ...
2
votes
2answers
331 views

Regulator and charging in a portable device

There are quite a few similar posts on this subject but I'm a little confused about the best way to proceed in my specific project. All my previous regulators have been linear types (eg: 7805, LM317 ...
1
vote
3answers
182 views

replacing disposable lithium-thionyl batteries with rechargable lithium batteries?

I have a device that takes 2 disposable 3.6 V 1/2AA 1100 mAh lithium-thionyl batteries and I would like to replace them with rechargable ones. It is a device that measures angles in wireless mode, and ...
10
votes
4answers
2k views

Pulse-powering heavy loads with a coin cell

Lithium coin cells are rated for fairly low standard current draws, on the order of 1 to 5 mA. Also, while they allow greater pulsed current draws (i.e., periodic bursts), this appears to be ...
4
votes
2answers
2k views

Making a lithium polymer circuit

I want to create a circuit that will power my Raspberry Pi using Lithium Polymer. My knowledge of LiPo is rather low and I believe they can get dangerous if used incorrectly so I turn here. THe ...
4
votes
1answer
1k 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 ...
4
votes
1answer
2k views

How much lithium in lithium polymer batteries?

This document summarizes aircraft travel guidelines for batteries: http://safetravel.dot.gov/documents/airline_passengers_and_batteries.pdf It has two categories of lithium batteries: 8 grams or ...
4
votes
1answer
6k views

How can I safely charge 3 lithium 18650 batteries to use in one pack?

I'm working on a project to make my own super-bright bike taillight using an emergency flasher LED (something like this:) The LED package requires a 12V input, but from what I've read from other ...
0
votes
4answers
1k views

Creating Li-Ion charger with step up to 700mA from 500mA?

Canon apparently hasn't ever herd of something called USB-charging. The factory AC adapter for this battery(NB-5L) output's 4.2V's at 700mA. Most standard USB chargers output 5V at only 500mA. Would ...
1
vote
2answers
757 views

What are the tolerances for the maximum current a battery can supply?

After a lot of research and experimentation I have come to learn that the sentence "This is a 1.5V, 2800mAh battery" is entirely a lie. (i.e., the potential difference between the terminals of a ...
4
votes
3answers
1k views

Lithium Button Cell Characteristics

I am working on a small wireless sensor platform and trying to figure out power supply options. My power budget is approximately: .2mA constant, ~15mA for .1s every 2-3s, and 60mA for 10s very ...
2
votes
1answer
340 views

MAX1555 Alternatives

As you know, the MAX1555 is a popular single cell lithium polymer charger. It can take USB power directly, restricting the charge current to 100mA or so. Are there any other MAX1555 alternatives ...
2
votes
2answers
932 views

Can I drop 4.5 V to 3.7 V with a diode?

I have an RC helicopter with a dead 250 mAh lipoly battery with a voltage of 3.7 V. Could I use 3 button cells at 4.5 V and a diode with 0.7 voltage drop to power the circuit, which is somewhat ...
4
votes
3answers
1k views

Smallest lithium battery backup?

I'm considering putting a small lithium battery on my Super OSD Pro boards. The battery would provide power to the RTC. I am wondering how small can you get a battery? I don't really care about ...