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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1answer
30 views

Help with charging lithium ion batteries

I want to make a lithium ion power bank. I have lots of lithium batteries but I don't have very many that are the same. So if I connect 20 different ones in a parallel circuit and they all have the ...
1
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0answers
62 views

Many questions about charging a lead acid battery

Well, I have a 12V 9AH SLA Battery, and I use a 7815 + a diode in series to charge it, (I really wanted to build a charger using the L200 or the LM317 but I couldn't find any of those in my city). So, ...
0
votes
2answers
31 views

Trickle charging a Li battery from motorcycle battery?

Sorry if this doesn't belong in the forum, however I'm unsure of where to start and am rather clueless with electronics, but keen to learn more. Essentially I would like to charge this GPS device ...
3
votes
1answer
62 views

How does a battery balance and protection circuit work?

I am building a 4S LiPo battery pack that I would like to incorporate in a portable speaker project and I need to make sure the batteries will never require maintenance beside replacing them ...
2
votes
2answers
85 views

Charging time of lithium ion batteries

I am charging a 430mAh lithium polymer battery at 1C using BQ24232 charger IC (from Texas instruments). The charge terminates within 1 hour 20 min with battery voltage showing 4.17V. On research I ...
0
votes
1answer
47 views

DC Bus for Solar Charge Controller Battery

I am just learning the set up for a back up power. I am just wondering whether the DC output from the charge controller or the battery can be used for multiple loads. For example, I want to power my ...
-6
votes
1answer
39 views

please help trying to figure out how long to charge [closed]

[![these are the specs][1]][1] I need help trying to figure out how long does it need to be charged? Also want to know how you figure it out for future reference
2
votes
0answers
61 views

Would this Li+ flashlight circuit be considered safe?

I recently got an inexpensive (~$4 USD) Li+ 18650-powered flashlight from banggood.com, one of my favorite sources for inexpensive Chinese electronics to tear down and hack for fun :) I wanted to ...
1
vote
1answer
29 views

Solar cell charging and battery chemistry for low power 2.4-3V supply?

I've recently been looking into the possibility of using an amorphous silicon solar cell (like they have in calculators) to supplement my very low power BLE system's current consumption to extend the ...
0
votes
1answer
53 views

Why the internal resistance of battery is greater than internal resistance of car's accumulator? [closed]

It is really important for me to understand the following question. I know that it is a basic stuff, but I think that I am still missing something. In my opinion it is caused by the fact that the ...
1
vote
2answers
69 views

Leaving NiMH and LI-ION powered devices (toothbrush) at charging station [closed]

So I have 2 sonic toothbrushes, one powered by NiMH the other by Li-ion batteries (waterpik & philips). The base stations (with charger in them) look so convenient and just lure me to store ...
0
votes
1answer
47 views

Battery charger disconnection

In modern devices (mobile phones, tablets, laptops) the battery charging current is automatically switched off when the battery reaches 100 %. After being disconnected, the power supply cools down. It ...
0
votes
1answer
35 views

Combining single cell LIPO chargers into a multi-cell charger

I have a 2S lipo battery that I want to charge. Normally, I'd charge it with a balanced 2S lipo charger like this, but for my application, I want to embed the charger in the device, and consumer ...
0
votes
0answers
23 views

Premature battery discharge

I bought a brand-new 7.4V 3000mAh 20C Turnigy lipo battery, and I'm using it to power a Raspberry Pi through a 90% efficient 5V UBEC. The Pi consumes on average 600mA, so I was expecting the battery ...
0
votes
1answer
40 views

Charge CR927 battery with small solar cell? [closed]

I am developing a Bluetooth tracking device that uses a single CR2032 battery. Would it be worth using instead a rechargeable CR927 (40mA) battery and a small solar cell, the size they put in watches? ...
0
votes
0answers
61 views

DIY Powerpack 18650 4s3p 14.8V charging

I plan to make a portable audio system with 4 speakers and a subwoofer which are driven by a 12v TDA2030A 2.1 Amplifier. Everything is already packed in a small enclosure (approx. 30x15x30cm) and ...
2
votes
2answers
225 views

Is it possible and safe to charge a NiMH battery with this circuit?

I am trying to design a circuit to charge NiMH battery packs from 2.4V to 9.6V and also single cells. From what I have read about charging NiMH batteries, it seems that all that needs to be done is to ...
0
votes
1answer
50 views

DIY battery Pack Cell amperage difference

I have individually tested the capacity of ten 18650 batteries with my iCharger 4010. My question is, how much ampacity difference is ok when packing them in parallel ? The following are the readings ...
0
votes
0answers
31 views

Why is this LTC4010 charging circuit resetting?

I have designed the following circuit based around the LTC4010 battery charger IC. This circuit is essentially a direct copy of an example circuit from the datasheet. The target battery is an 18V ...
0
votes
0answers
26 views

Switch (safely!) between running/charging status with li-ion batteries (18650) in series

I am building a solar robot/car which is going to be solar charged (or alternatively usb, I can't detach batteries to charge with an external charger). I am using inexpensive parts such as TP4056 ...
0
votes
1answer
49 views

LiPo charging circuit

I'm using a 6s Lithium Polymer battery in one of my projects, and I'd like to make it more consumer friendly. This means that I should probably get rid of the need for a balance charger (which few ...
1
vote
2answers
49 views

Can I convert L-ion battery backup to supercapacitor?

I have a RAID card in my home server and the battery went dead. It's a lithium ion chemistry with the circuits to tell the RAID card miscellaneous information. I could buy another L-Ion battery to ...
0
votes
2answers
43 views

Why is it slow charging from USB compared to charging from the power plug? [closed]

It's almost twice as fast charging my phone directly from the power plug compared to if I charge my phone from the computer's USB port. Why? Isn't the charge the same or is it that USB has much lower ...
1
vote
1answer
224 views

What is the meaning of 25C?

I have a lipo battery of 11.1V,3s,5200mAH. What is the meaning of the 25C discharge current? How much current does it indicate? How do you interpret it?
4
votes
3answers
123 views

Light an LED when load is in circuit

I want to have a LED light up when a load is in circuit, and go out when it is not. Initially I set the circuit up so that the LED is in series with the load but this didn't work. I think possibly ...
3
votes
1answer
97 views

How deleterious is topping-off my Li-ion batteries (phone/laptop) every time they drop to 90%?

I have read recently that frequent top-off charging of my personal electronics is hard on the batteries. Specifically, Li-ion batteries in recent model smart phones and laptops will show significant ...
0
votes
1answer
26 views

Simple and easy-to-charge battery for a DIY power generation project with varying voltages and currents?

I'm converting a decorative windmill to a power generation device. I'm looking for a battery that can charge with wildly different voltages and currents and be simple and easy to charge. It doesn't ...
-3
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0answers
31 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
129 views

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

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
47 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
9 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
59 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
59 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
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1answer
75 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 ...
1
vote
1answer
95 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
50 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
86 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
44 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
52 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
79 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
44 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
39 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 ...
0
votes
1answer
53 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
37 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
50 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
108 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
59 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
34 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
69 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 ...
1
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2answers
55 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.