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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-3
votes
0answers
29 views

12 volt dc power supply using smps

Sir I would like to make a 12 volt dc power supply using old pc smps. As we know the black wires are common and yellow wires are 12 volts. My question is if I separate those wires and make terminal to ...
0
votes
3answers
116 views

Can I charge a 12v toy with USB? [on hold]

I have this small palm sized toy drone. It uses a 'charger' which houses 8 AA alkaline batteries. The charger plugs into the drone and the charger is activated by a toggle switch. I want to replace ...
0
votes
1answer
40 views

One battery discharges faster than the other in my solar power system

So, I have solar power system and it is as follows: 2 AGM batteries each 100 Ah 2 solar panels 24-Volt , 250 Watts each a controller an inverter the batteries are connected in series to give a ...
0
votes
0answers
8 views

Low output voltage on load sharing battery managment IC?

I have a battery management IC with load sharing (MCP73871) connected to a 5 V input. When I don't have a battery connected, I expect the IC to pass 5V through to the output. Instead what I'm getting ...
1
vote
2answers
45 views

charge 5v battery with 12v solar panel

I've a 5v 2200mAH battery and a 12v solar panel and charge controller. Is there any danger in charger my battery from the 12v panel/controller? The batter will then power my raspberry pi zero ...
0
votes
3answers
52 views

Looking an IC chip to charge cell phone [duplicate]

I have a DC voltage source (between 5 and 10V) from which I want to charge cell phone with a USB cable. I believe that using a LM317 or similar IC for charging cell phones is not a good idea as most ...
1
vote
1answer
58 views

About 18650 batteries possible accidents with reversed polarity

We all know that lithium batteries are dangerous and can blow up if we use them the wrong way. My doubt is, if I accidentally place them in the following sequence in series (Pay attention to the ...
-2
votes
1answer
29 views

Voltage regulator needed for charging rechargeable battery via solar panel? [closed]

I want to charge a 12V rechargeable battery (3Ah) with my solar panel - link to eBay site. Do I need to add a voltage regulator to charge the battery? Would it destroy the battery without one?
1
vote
1answer
62 views

How to charge a lipo battery inline with load

How do you charge a lipo battery while it's still connected to it's load (e.g. like all modern mobile consumer electronics) using an off the shelf lipo charger? I have an Accucell S60 battery charger ...
0
votes
1answer
44 views

Voltage regualtor with 5v output @ 2.5 amps [closed]

I did some research online and could not find an answer to this. I have a 6v @ 12Amps(I think its 12amps) battery pack with 4 Super heavy duty d-cell panasonic batteries(1.5v each). I want to use it ...
-2
votes
1answer
67 views

Charging a 3.7 V with a 5V usb charger [closed]

For a project, I want to charge a lipo battery (3.7V @2000mah) with a 5V USB charger. I'm not into electronics, so I don't know if is viable to do that. So, can I charger a 3.7 battery with a 5V ...
0
votes
0answers
34 views

TP4056 - Increasing charging current

I am designing a Lithium Ion charging circuit that will be using the TP4056. Currently, the peak current is 1A, and I would like to increase the charge current in order to complete the charge faster. ...
1
vote
1answer
43 views

Non-led simple bicycle dynamo light system

There have already been questions about how to build a bike power supply based on the bikes dynamo. Most of the answers contained lots of basic components. Some answers here are making a full wave ...
1
vote
2answers
71 views

Battery Charging Time Computation

Good Day, I am having trouble to compute the charging time of my battery with this kind of set-up: (2) 300W 36V PV Panel (1) 500W 24V Wind Turbine (1) Hybrid Charge Controller (6) 12V 200Ah ...
-2
votes
1answer
34 views

Which better charge method for 12v 10w solar panel to 2x 6v 4.5ah battery?

i have 12v 10w solar panel and 2 x 6v/4.5ah battery. Im planning to build control that charge 12v battery (in this i series 2x6v battery) and after i read this Do batteries in series equalize charge ...
1
vote
1answer
38 views

Charging series connected batteries independently

Just want to make sure this charging configuration will work. Basically we have two solar panels and two solar charge controllers independently charging one of the two series connected batteries ...
1
vote
1answer
44 views

Inductive Charging Mouse [closed]

I recently bought a wireless gaming mouse and while functionally its great, the battery life is a little less than I would like. I tried to mitigate this by adding in another rechargable AA battery ...
0
votes
2answers
35 views

single cel 3.7 V 2600 mah with 19v charger how is this possible?

i have a Bluetooth speaker that uses a single cel 3.7 2600 mah battery but the charger says is 19V and i have read that the max volts to charge 3.7 V is 4.2 V, so how is this possible? now im ...
1
vote
0answers
44 views

Lithium Polymer battery puff sensing

I have an IoT application which requires > 20,000 mAh of battery capacity. This can either come from a single cell or a number of cells connected in parallel. The device is going to remain unattended ...
-5
votes
2answers
103 views

Calculate ampere using volt? [closed]

Can we calculate the output ampere of a battery charger by calculating battery voltage over time: 1. Get volt value name it volt1 2. Wait a second 3. Measure volt again name it volt2 So would the ...
0
votes
1answer
41 views

Battery Protection IC: How to ensure that even under-voltage batteries are allowed to be charged?

As I understand, the battery protection circuit isolates the battery from the battery connector if it detects undervoltage condition. If this happens, how can the system ever charge the battery and ...
0
votes
1answer
33 views

Using half of a series circuit

I have a UPS that has two 12V batteries wired in series. I'd like to pull 12 volts off of one of the batteries to directly run some 12v DC equipment without going through the built in UPS AC inverter ...
1
vote
2answers
58 views

Overcharged NiMh batteries + Servo

I have 2 NiMh batteries 3500mAh 7.2V. However, first one have 7.58V(it increases each time Im measuring it) and second one have 8.37V. Can this be the reason why 5x servos are doing unexpected ...
0
votes
0answers
11 views

Can you charge an electric motorcycle at an electric car charging station? [migrated]

Do electric motorcycles and cars use the same type of chargers? Can we charge a Zero motorcycle at a Tesla supercharger station? How about at an electric car parking?
1
vote
2answers
44 views

How to check what is the percentage of charge in my lead acid battery?

http://www.allbatteries.co.uk/media/pdf/AMP92108_FR.pdf I want to know how much percentage of the battery charge is left without buying any fancy equipment to measure it.
0
votes
2answers
67 views

What voltage and current do I need to charge a 4V Acid Battery?

I need to charge a 4V Lead Acid battery, but it is not clear what charging current and voltage I need. I checked many datasheets for 4V acid batteries, but I did not find anything that determines ...
2
votes
2answers
152 views

Eliminate standby leakage current of output capacitor in a DC/DC converter charging a battery

I am using a DC/DC converter to charge a battery. The output current of the converter is about 6 Ampere at 41 Volts. I'm trying to eliminate the standby leakage current of the output capacitors in ...
0
votes
1answer
97 views

Confused about battery voltage warning circuit with PNP transistor and Zener diode

Below is a circuit where an LED will light on when the battery voltage (Vcc) is below approximately 8.8V. However, I'm confused as to how it works. My understanding is that when the battery voltage is ...
0
votes
1answer
122 views

TP4056 Lithium Charger Module issue

Im having an issue with TP4056 Lithium Charger Module. Connected the battery 3.7v 150mah battery. When charging the red led is on but it never shuts off and no charge state is reached even after 1-2h ...
0
votes
2answers
42 views

Replacing power transformer with SMPS to charge SLA battery

Item: 25W amplifier/speaker with SLA batteries. I've done a little bit of modding in there. I doubt the warranty is valid any more, lol. In case you don't want to read the link about my modding, ...
0
votes
1answer
36 views

Can I charge multiple SLA batteries at once like this?

Simple question from a beginner. I 'drew' a schematic diagram to show my idea of how I could charge multiple SLA batteries with a single charger. Would this work if I solder the wires together as ...
0
votes
0answers
30 views

Solar charger reading at battery terminals

I have a 15 watt solar charger and a deep cell AGM battery. After sitting for about a year, the battery was reading 12.45 volts. Connected to the charger in full sun (with a charge controller ...
0
votes
1answer
47 views

Switching Lead-Acid battery charger

Sorry if this question is a bit broad, or too part-suggestiony. I've been trying to find a good solution for over a month (and three board revisions) now, and I hope someone has an idea I haven't ...
0
votes
2answers
66 views

Charging a car battery with two chargers simultaneously

My car, which has a 12v silver calcium battery, is flat and I would like to get on the road as soon as possible. I got two car battery chargers that are not identical, but both can operate at 6 an 12 ...
1
vote
1answer
51 views

High-voltage cutoff for battery charger necessary?

I'm trying to build a treadle-powered general purpose USB charger. Internally, the treadle spins a motor which feeds through a diode bridge to charge up a storage battery. The battery then discharges ...
1
vote
1answer
54 views

making battery charger for lead acid battery 6v

Hello so I was just given a 6v 4.5 Ah (4500mAh) sealed lead acid battery. I have never made a battery charger before but would like to make one now for this battery as it is for a robot I'm building. ...
0
votes
1answer
25 views

MPPT for fixed DC use, or charging multiple independant batteries at once?

I've got a set of small deep discharge lead acid batteries (7ah @ 12v) and a few larger ones that I use for running electronics in remote areas for hobby use. I don't use them evenly throughout the ...
5
votes
3answers
2k views

Why some phones need a 5V charger although the battery needs 3.7V only?

I've many mobile (smart phone) chargers. The output of them is 5 volts but the battery needs 3.7v only. Why is it better to make a 5v charger then convert the 5v to 3.7v ? Why don't we just make a ...
0
votes
2answers
40 views

Voltage level when connectiong two power sources [closed]

I've experienced the following situation the other day. When connected to this smart powers charger (never seen one of those), the battery voltage dropped. Made me wonder about two questions. 1. ...
3
votes
2answers
97 views

What Circuitry is needed to charge in parallel, but power in series?

simulate this circuit – Schematic created using CircuitLab I've read several other battery posts, and didn't find the answer I was looking for. My question is, can the Diagram I've ...
1
vote
2answers
77 views

Why rechargeable batteries use 1.2V

I have noticed that AA (or AAA in that case) rechargeable batteries are always of nominal 1.2V while non-rechargeable have nominal voltage of 1.5V. This works just fine in some cases, e.g. when the ...
0
votes
1answer
83 views

Some 12 volt sealed lead acid battery questions

(Update posted at bottom, I think it's solved but still open to advice) I recently received 2 12v 7ah batteries I ordered to replace the old ones in an electric skateboard. Upon receiving them, I ...
0
votes
1answer
57 views

Discharge Characteristics of Lithium Ion Battery

I am doing a simple experiment to analyse the discharge characteristics of a Lithium Ion battery to see how long it takes to discharge. I have a 12V 4000mAh battery. Once charged, using a voltmeter I ...
0
votes
1answer
59 views

Will this Solar-Electric hybrid circuit work?

Would the circuit above works? I'm trying to build a self sustaining solar powered Arduino controlled plant watering system. Since I'm using an electronic valve and not a pump, I'll assume it ...
1
vote
2answers
94 views

Can solar panel charging slow down the draining of phone battery? [closed]

I have made a solar panel charger, it consists of a 1.2 watt panel connected to a buck converter, then to the phone. Now, when I connect it, it charges the phone and in the battery settings it shows ...
0
votes
1answer
48 views

Battery Charging Currents

I know that when charging a lead acid battery, there are 3 stages, 1.Constant Current 2.Topping 3.Float. Referring to this image, I can see that there is some current, 1A in this case, ...
-2
votes
2answers
162 views

Battery Charging circuit problem

I want to charge a 3.7v battery of 3000mAh. I am using the battery charging circuit based LM317(from internet source) I have connected the components by supplying input voltage of 9v and while ...
2
votes
0answers
102 views

Lead-Acid Battery Desulfation Circuit Design:

I'm seeking ideas for making a pulsing lead-acid desulfation circuit design. Several circuit designs are available via Google image search, however, I'm hoping to get some help here to design a ...
2
votes
2answers
165 views

Replace foil caps with ceramic caps?

I am repairing a battery pack (see below) which has some old foil capacitor (100nF) between a sense Terminal and the negative (together with a NTC thermistor). Can I replace the foil cap with a X7R ...
-3
votes
2answers
50 views

What happens when the battery is being charged? [closed]

Do the electrons move back to the negative terminal?