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).

learn more… | top users | synonyms

0
votes
0answers
21 views

About Battery Balencing

I have one doubt ,i have two Li-ion battery in series and even I'm charging battery's with a charge controller ic ,the doubt is how can i balance my two battery on same voltage with out any ...
0
votes
0answers
14 views

Switching Battery Charger IC

I am looking for a smart switching battery charger IC that manages the charge cycle for me. Its for lead acid, 24V batteries. 1A 'fast' charge cycle followed by a float (or trickle) charge. The ...
2
votes
1answer
34 views

Noobie is trying to match a solar power bank and a wireless camera

my dear friends all around the world! I'm very interesting about this cool solar power thing, and I really want to start connecting all of my stuff to panels and so. But for my first and ,hopefully, ...
0
votes
1answer
49 views

Need help how to backup cellphone… i need output power 5v 1a from AA battery

How do i get the amount of 5v 1A for my backup battery for my cellphone unit? from 4pcs of AA battery(each batt is 1.5v 2500mAh) to 5v 1A been searching for a while ago 1,is it better to use a 7805 ...
0
votes
0answers
39 views

Lipo battery powered UNO : charging and using at the same time

I have a 3.7V Lipo battery hooked up to a 5V step-up converter that goes into the 5V pin of my Arduino. So far so good. My goal is to use the battery only when there is no external power for the ...
1
vote
2answers
44 views

Separating power ground from control ground

I'm looking at the 'layout considerations' for TPS61030. On p.18, it says Use a common ground node for power ground and a different one for control ground to minimise the effects of ground ...
0
votes
2answers
28 views

How is the resistor value for boost conversion calculated?

I'm looking at MCP1640 and in Section 5.2, an equation for calculating RTOP is presented. However, the two examples underneath have RBOT = 309kOhm. How did that come about? Is 309kOhm some standard ...
0
votes
2answers
46 views

Portable phone/device charger

I am doing my best to make a portable charger. Here is the link with the schematic of the circuit I am working on:Voltage regulator question .I was told that the 9 V battery I was using didn't have ...
1
vote
0answers
56 views

Reverse current frying a boost converter?

AFAIK, most boost converters incorporate a diode or some mechanism for ensuring that current flows from the battery to the output. For instance, TPS61030's datasheet says that This device however ...
5
votes
2answers
261 views

Logging lithium battery discharge: why this curve?

I'm using Arduino to log the discharge curve of a 5V battery pack (usb type for smartphone recharging). Using Arduino I read the voltage every second and I save it to a log file. Arduino is powered ...
0
votes
2answers
41 views

Charging Li-Ion cells

I have 6 18650 Li-Ion cell from a very old Dell laptop. Unfortunately I could not find any info about them from their markings. They were connected as 3S2P with a total of 11.1V and 4700mAh. ...
0
votes
0answers
19 views

Powering a 5V device from one or more sources

I'm building a circuit and need to power a PICAXE IC from one of two possible sources - a USB 5V connection (which provides power for the Adafruit Powerboost 500 charger), or a Raspberry Pi, which ...
0
votes
0answers
60 views

I want my cellphone battery to remain useful for five years; please advise me on how to achieve such a feat [migrated]

I own an Android smartphone with a lithium-ion battery. I want its installed rechargeable battery to remain at least somewhat useful for five years, if possible. (Other people aren't so careful; ...
4
votes
3answers
540 views

Regulating AA to 5V and achieving high efficiency

I'm trying to regulate a single AA battery to 5V for charging a USB device. I know even at perfect efficiency, it won't provide much juice (1.5v * 1500 / 5v). But what is the expected efficiency for ...
0
votes
3answers
102 views

How does charging a phone battery work?

For example, if a phone comes with a charger rated at 5V and 0.7A, when it's plugged in to charge, what dictates the current the phone draws, is it the resistance of the phone? If I = V/R, do phones ...
1
vote
1answer
30 views

Charging circuit for a small capacity (13 mAh) li-ion battery

I got my hands on some of Panasonic's new "pin-type" li-ion batteries – the CG-320. However, I have never had to charge a battery with such a low capacity (13 mAh). Are there charge management ICs out ...
0
votes
0answers
53 views

SLA (Sealed Lead Acid) Battery Float/Trickle Charger Design

I would like to replace an unregulated transformer-based built-in charger in an emergency LED lamp. The biggest problem with the original charger is that when the current tapers off, the voltage ...
0
votes
3answers
55 views

Power a Micrcontroller Using a 12 Volt Battery

I have a solar panel that is charging a 12 volt battery through a charge controller. The battery is used to apply voltage to a pump. I would like to use the battery to power the micro-controller. What ...
0
votes
0answers
21 views

Retrofitting synthesizer with internal uninteruptable power supply?

I have an old Roland synthesiser (MC-909 sampling groovebox) that I would like to retrofit with a backup battery both to avoid loosing work and just so I can take it down the park with some ...
0
votes
0answers
24 views

Can't MCP73871 directly power a load?

I'm looking at lady ada's PowerBoost which uses both a MCP73871 and a TPS61090. Why is the TPS61090 needed? Can't the MCP73871 directly power the load? If I'm reading it correctly, the design doesn't ...
0
votes
1answer
21 views

Load regulation and battery charging

With the MCP73871, the load regulation is 0.08%. Does that mean it expects the battery voltage to increase strictly monotonically? That is, if the device consumes 2000mA at 5V (around 3000mA at 3.7V) ...
0
votes
1answer
47 views

Can I reinsert a partially discharged 12v battery back into a solar battery bank? [closed]

These two questions are close to what I'm asking, but I'd like some specific clarifications: How do we charge a small 12V battery from a large 12V battery bank Increase the capacity of a 12v battery ...
0
votes
0answers
15 views

Effect on ambient temperature on Battery (lead acid, AGM, lithium)

Most of the manufacturers state the number of cycles for batteries at a temperature of 27 degree celsius. My question, how will the batteries (Lead acid,AGM,lihtium) be affected when charged/operated ...
0
votes
2answers
39 views

LiPo charging in consumer electronics (less than 1C?)

At what (max) rate LiPo batteries in consumer electronics are charged (for example in cell phones). I mean that LiPo-s are dangerous when overcharged, so what is the best charge rate to be absolutely ...
0
votes
0answers
44 views

How to calculate run time of inverter

I have a 24volt inverter (2kva). There are two 12V, 200AH AGM (C20 at 27 degree c)batteries connected in series to the inverter input. Now, if I have a constant load of 2.5 amperes at 120V, how do I ...
0
votes
1answer
90 views

12 Volt Solar Air conditionair

I saw a post on YouTube where somebody was able to make ice with a 90 watt solar panel, two 12 volt batteries, an ice maker (800 watt spikes) and 1000 watt DC-AC inverter. ...
0
votes
1answer
70 views

Running the AC overnight in an EV car [closed]

I've heard we will have EV cars (not hybrids with small combustion engines) that can drive 200 miles between charges soon. I was wondering about the battery cost (in terms of dissipation) if you were ...
0
votes
1answer
35 views

battery chargers - AGM and lithium

I am working on an inverter with a battery charger for a 24V,200AH AGM battery pack. The battery charger current can be adjusted from 10 to 50 amps. Now, I want to be able to also a charge a lithium ...
0
votes
2answers
73 views

Lithium Ion battery charging

Its just a simple Question Lets Say, I have 4 x Lithium Batteries each 6800mah capacity and Lithium Battery Charger IC BQ24618 from texas instruments. Will I be able to charge these batteries ...
0
votes
1answer
29 views

LiPo charging module used as backup?

I am running small stm32/gsm module project and would need battery backup in it. Is it possible to use cheap lipo charging module to do exactly that. I would charge my battery through input terminals ...
1
vote
1answer
36 views

How to connect Li-ion batteries with thermistor pin in parallel?

I have a Li-ion charger with 3 contacts: (+) (-) and (TH), based on TP4056 chip. I also have several batteries with corresponding contacts, and the charger does a good job charging them. Now I would ...
0
votes
0answers
40 views

How to find the cut off and maximum voltage rating of a battery

How can I find the cut off voltage of my battery (for discharge) and a maximum voltage (for charging)? Is there an equation to do this, or are these two calculate by making a discharge curve? Thank ...
0
votes
1answer
47 views

How to make a voltage vs amp-hour discharge curve

This is in regard with another question of mine, how do you make a discharge curve with the y-axis of voltage and x-axis of amp - hour?
0
votes
1answer
48 views

How to make a discharge curve

I am trying to make a discharge curve for one of my batteries that I have. All I know about it is that it is a 1.5V battery. Now if I have to make a discharge curve for it, how would I make one and ...
0
votes
0answers
49 views

Is it safe to charge ion lithium batteries with a higher current power supply?

I'd like to know under which circumstances it is safe to use a 5V charger for a device which has a lithium ion battery with an higher maximum current than the correct one. I ask this because I tried ...
1
vote
2answers
75 views

How to charge an AGM battery fast?

I have a 12V, 200AH AGM battery. The maximum charging current recommended by the manufacturer is 50 amps. Now, I need to connect two AGM 12v batteries in series to connect to the input of my 24 volt ...
0
votes
1answer
46 views

Battery charging- Float mode and boost mode

Based on my knowledge on batteries (AGM), the initial battery charging (for ex. a 12V, 200AH battery and a 24V, 20 amp charger ), takes not more than 2-3 hours for the first 70% charge and then it ...
1
vote
2answers
133 views

Do I need to fully drain lead acid battery before charging them? [closed]

This is a follow up question based on this. I have an ebike which uses lead acid battery, my question is do I need to fully drain it before charging it again? How about when the battery is newly ...
0
votes
0answers
33 views

Charging AGM batteries

I have a 24V, 120 Volt/60 Hz inverter. I have two 200AH, 12V AGM batteries connected in series. I want to charge these batteries completely in 5 hours or lesser. What voltage and current should my ...
-3
votes
1answer
106 views

Why does the Apple Watch use a wireless charger, even though such a charger works slower than a MagSafe-like wired connector would? [closed]

The Apple Watch includes a built-in lithium polymer battery (a few hundred mAh; slightly more than 3.75 V) which is recharged using a wireless inductive charging cable. The cable does use magnets to ...
0
votes
1answer
32 views

Number of cycles for AGM battery with an inverter

I have an AC system which has a continuous load of 7 amps at 120 volts. To run this system, I need a set of AGM battery and an Inverter system (power factor- 0.8). The inverter is 24 volts and rated ...
0
votes
2answers
120 views

Derivation of Formula

This is the method for calculating the State of Charge (SOC) of the 12V lead acid vehicle battery. Based on the formula for battery capacity (C) formula $$C = (\text{Current}) \cdot (\text{Time of ...
3
votes
1answer
68 views

Multiple charge controllers on the same solar panel

I have two 12v lead acid batteries on my boat. One at the front for the trolling motor (~80 AH) and 2 smaller batteries in parallel at the rear for electronics (~30-35 AH combined). I want to put a ...
-1
votes
2answers
58 views

Can I charge two small batteries of different voltage using one solar panel and two diodes?

If I use diodes to direct power to each of two small batteries (old NiMH laptop packs), will both charge properly from a single solar panel at the same time if one pack is 11 Volt (9 NiMH cells in ...
0
votes
2answers
92 views

What is the deal with input voltage?

Let me tell you right off the bat that I am new to electronics, more specifically the creating of electronics. I recently discovered a project that I would like to make, a pocket power supply(link at ...
-4
votes
2answers
55 views

Connecting a 20 amps battery charger to an 18 amps source [closed]

I have an inverter with a 20 amps DC battery charger (AC to DC ). I need to a connect the ac Generator output to the ac input of the inverter. The thing is that the generator can provide a maximum ...
0
votes
2answers
110 views

How could a rechargeable battery charge itself without an external source?

While I was working on my graduation project I had to charge a rechargeable battery then discharge it and so on.I was shocked when the battery charged itself without any other external sources for ...
0
votes
1answer
42 views

Charging Indicator for any battery (Charge Monitor)

We see in all today electronic devices like mobile a Visual battery charging indicator,that a graphical Container composed of bars that increases one by one when the battery is charged for long, and ...
1
vote
1answer
79 views

How to calculate solar panel setup?

I have an equipment which draws 550W at a constant level, no peaks. I want to power this unit with solar cells only during the day when there is light using a simple car battery. Because I don't want ...
0
votes
0answers
9 views

Question about Solar Panel and Lithium charging board

I have a 6V 4.5W solar panel which I would like to use to charge my Lithium-Ion batteries. The battery chargin board accepts 4.5-5.5V. Would it still be safe to use it with 6V? If not, should I just ...