Please specify the battery type in your question. Include chemistry (e.g. lead-acid), voltage, number of cells and how they are connected (series or parallel), capacity (in A·h or W·h).

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0
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2answers
24 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
votes
3answers
80 views

How can I make a safe Ni-MH charging station?

I wanted to make a docking station for my robot. My idea was simple - robot drives in, batteries are disconnected, pins that I attach to my Ni-MH charger's electrodes are inserted into battery pack, ...
0
votes
2answers
68 views

How is this 3 VAC power supply charging this 18 VDC battery? [closed]

My cheapo 18V Black and Decker cordless drill recently died, and thinking I could maybe fix it, I took everything apart and then couldn't figure out how it was ever working in the first place! Here's ...
0
votes
2answers
63 views

Differences between 5V DC 350ma vs. 450ma [duplicate]

I have two A.C adapter chargers giving an output of 5V DC 350mA and the other one with 5V DC 450mA. Is it possible that I could ...
1
vote
1answer
30 views

Using current measurments for smart charging a battery

I've been doing some reading on smart charging a battery, and I hope to create a system that can charge batteries with the use of a solar panel. Most of the reading I've encoutered utilises the ...
0
votes
3answers
62 views

Can I use + charge 3 LiPo cells in series with 3 separate charge controllers?

I'm looking at this circuity from SparkFun. It's an mppt + LiPo charger, which is exactly what I need, but I need several cells. I'm actually fairly content to just build 3 of these, and wire each in ...
1
vote
2answers
52 views

Charging NiMH Batteries

I'm wondering if MAX712 would charge 4 Eneloop batteries in series. I don't know if it will charge them safely and if it will charge them the correct way. How much voltage will need to be provided to ...
2
votes
1answer
50 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 ...
2
votes
1answer
119 views

Charging 10 1.2V nicd batteries

I have 10 x 1.2V Sanyo NiCd batteries. They are connected in series. I would like to charge them. The thing is, I don't have a charger. I looked up chargers and they are all quite expensive(I live in ...
0
votes
1answer
84 views

Charging batteries in series when they are connected in parallel in the circuit

I'm new to electronics and I'm trying to build a charging circuit for NiMH batteries. There are four batteries in total. Two are in series, and the other two are in series. Then these are connected in ...
1
vote
1answer
54 views

Question on 3DS power adapters, minor voltage difference [duplicate]

I am going to be traveling overseas and bringing my Nintendo 3DS which the adapter outputs DC 4.6V 900mA. I found an unofficial USB cable to charge it and I was curious if the minor variance in the ...
0
votes
0answers
59 views

Effective power circuit for currents up to 1.5A and with battery charger (PMIC or not to PMIC?)

For my ARM-based (A10) device I need to create power circuit. Input voltages: 5-28V, may be charging from USB. Output voltages: 5V, 3.3V, 1.2V, maximum output current -- up to 1500mA, working current ...
0
votes
0answers
36 views

Automatically changing currently used and charged deep cycle batteries, any problem?

I don't know the internals of commercial solar deep cycle battery chargers, though mostly what I see in home made ones is that a regulator circuit is connected to battery, and when you want to use the ...
0
votes
1answer
43 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?
1
vote
1answer
42 views

BQ2407x Li-Ion charging circuit, what if Vin is disconnected?

We will use a Texas Instruments BQ24072 in our power board to monitor the battery. -PoE or solar will charge -Most of the time, circuit will work on battery. When disconnection the Vin, one would ...
2
votes
3answers
135 views

How do USB charging and “smart” charging ports (e.g. Anker's PowerIQ) work?

Software engineer with a hobbyist understanding of EE here. I've noticed lately lots of claims from producers of USB battery packs that their ports are "smart" and "identify the device" to "deliver ...
0
votes
1answer
44 views

Faster charging of Lithium Polymer battery possible?

I am designing a system which needs to run for 3 minutes, then charge as quickly as possible, then run for 3 minutes, then charge as quickly as possible, and so on. In order to reduce the charging ...
0
votes
0answers
49 views

Designing an Automated Switching System for Solar Battery Charging Station

I am trying to design an Automated Switching System for my Solar Battery Charging Station project. In the project a 48V battery rail is charged with two 200W panels connected in series through a PWM ...
1
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2answers
77 views

Why one transistor switches on first than other

In the circuit diagram given below we have two transistors. And in the article it is given that one transistor will turn on first. Why this transistor turns on first
2
votes
4answers
225 views

Need help explaining this circuit and how it is dimensioned and designed

I'm working on a project to school where I'm designing a battery charger with battery status indicator, and I found this circuit online: but to include it in the project, I must explain how it ...
2
votes
0answers
66 views

Li-ion battery calibration technique

As you know the li-ion batteries have flat voltage curve and it is not possible to detect battery state of charge (SOC) from voltage accurately. We use fual-guage which measures the accumulated ...
1
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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
votes
1answer
97 views

Charging battery using computer power supply?

I have new 600W ATX computer power supply unit. I have wired green and black together to make power supply turn on when plugged in. I wanted to charge my 12VDC empty battery, without dealing damage to ...
1
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2answers
90 views

Watts in Solar Panels

How does the amount of watts affect a solar array? The solar array I found is 14 W, so what would I encounter if I purchased an lower/higher wattage? I'm going to purchase an array to charge my ...
-1
votes
1answer
78 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 ...
0
votes
1answer
83 views

How can I modify the charging circuit of the solar powered system using super-capacitor with or without battery (diagram is attached)?

I 'm working on a device which according to the below diagram, has a solar panel witch gives at most 10v voltage and 30mA current (average 9v and 20mA) and also it has a 6v lead acid dry battery with ...
0
votes
1answer
62 views

Solar panel & battery math verification

I'm looking for confirmation to see if this battery and this solar panel will cover my needs for a remote timelapse project I'm setting up. The timelapse will run 6 days a week for 9 hours. My area ...
0
votes
1answer
56 views

Can someone tell me if this topology for a crude battery charger is sound? Block diagram included

I am making a portable phone charging battery for fun. I have a micro USB input that ties to a 5V - 4.2V buck converter to charge a li-ion battery. The IC is made to charge batteries so I think that ...
2
votes
2answers
143 views

Effects of continous slow charge on a battery?

If you connect a solar panel to a phone battery, but the solar panel provides about 1/4 (or 25%) of charge (mA) compared to the battery's original charger. Will this slow power charge the battery ...
1
vote
2answers
103 views

DC-DC converter to drive DC motor

In a robotics application I have to install a 12V (30A) DC motor actuator in a vehicle. The typical setup indicated by the manufacturer is to directly connect it to the battery, because of inrush ...
0
votes
0answers
45 views

Equations to charge a lead acid battery with constant voltage strategy

Typically there are 3 zones to charge a lead acid batteries.In the first step, the battery would be charged with a constant current and after a specific SOC, constant voltage strategy would be applied ...
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
2answers
80 views

How does this shunt regulator work?

I'm investigating battery monitors and I'm looking at TI's BQ76930 to take care of an 8 cell 24V LiIon. They provide the datasheet for their evaluation module (PDF warning) which includes the board ...
3
votes
1answer
55 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 ...
1
vote
0answers
64 views

Rechargeable battery with a photovoltaic switch

I did some searching around on the forum but with absolutely no electrical background, I have exhausted my searching and hope I can explain my issue. What am I trying to do? I have a solar panel and ...
2
votes
1answer
132 views

Charging High Cell LiPo batteries

I have a question about charging and balancing a 10-12 cell LIPO battery. I have been searching around for an all in one solution chip but come up empty. I have also found out that there are almost ...
0
votes
1answer
63 views

Efficient high amplitude current regulation, so I don't end up being sad

I have an unstable power source 0-10V (I don't actually know if it can drop to 0) from solar panels and I want to boost and stabilize it to charge 19V 2.1A laptop and a 12V 12Ah battery. I've already ...
0
votes
1answer
94 views

Is it OK to trickle charge a disposable battery [duplicate]

So I am playing around with designing a UPS when another question hit me. If I have a source feeding a small amount of current into a non-rechargeable battery is this OK. By OK, I mean is this ...
0
votes
2answers
332 views

Are AA battery and 18650 battery the same? [closed]

I have an Antex SZ004W0 wireless soldering Iron which uses three 1.5V, AA batteries, but I don't know if it supports rechargeable batteries. I know that it supports non-rechargeable battery named ...
0
votes
2answers
159 views

How do I make a circuit that charges two 3.7 Li-Ion batteries (in series) with a 5v input?

I want to make an Arduino wristwatch that can be wirelessly charged by inductive charging. The two 3.7v Lithium Ion button cells are hooked up in series (to make around 7.4v) which powers my Arduino ...
1
vote
1answer
125 views

How efficient is wireless electricity compared to wired electricity?

I am looking for data showing practical data/information on the efficiency of wireless (induction) transfer of electricity vs. wired transfer. There is some information out there but the source makes ...
0
votes
4answers
415 views

Why does my DIY “solar panel circuit” show battery voltage and not solar panel voltage?

I've got two solar panels set up in series as shown on the below schema. I connect positive on panel A to positive on battery, and negative on panel B to negative on battery. The two panels produce 9V ...
2
votes
2answers
145 views

Battery charging and discharging problem

I have designed a battery charging and discharging circuit. The main purpose of this circuit is to charge the battery and then discharge, one operation at a time. I have also added a hysteresis of ...
2
votes
2answers
121 views

How to store the electric energy produced by solar panels properly?

I am building some solar panels from 6" cells (4W, 0.5V, 8A). At the moment I have two 1x2 panels and one 2x2 panel. So there are 8 cells in all panels and the added voltage is up to 4V. Now I want ...
2
votes
2answers
137 views

Ni-Cd battery is not working properly [closed]

I have a Ni-Cd battery (8AA) 700 mAh 9.6 V, taken from an RC car. However, is no longer capable of powering up sufficiently the RC car. Specifically, servo works fine but motor can't spin. Instead, ...
0
votes
1answer
64 views

Lead-acid battery charging [closed]

Have an unbranded lead-acid battery charger and a small 6Ah 12V battery. After about a year of purchasing the set I need to charge it for the first time. For car battery jump start I vaguely remember ...
1
vote
1answer
426 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 : ...
2
votes
1answer
105 views

LiPo use while charging: two cells (one charging, one under load)

I'm trying to figure out how to power my project using LiPo batteries and a solar charging circuit. The project will draw up to 2A at 3.3V. I did a search for IC LiPo charging chips that also allow ...
2
votes
1answer
103 views

Combine 2 circuits to get the best of both? Battery management system

I'm working on a battery management system for 2 12V batteries in series, totalling 24V, and I found this very good blog online with 2 circuits that got me very interested: This one, that got me for ...
0
votes
1answer
99 views

Bus and self powered device using FTDI FT230X

I'm trying to wire up my first device using an FTDI USB to Serial converter. FTDI recommends not mixing bus and self powered designs. But they also mention that it's possible in the documentation. My ...