battery charger

  1. Pranav Sant

    How to charge a battery with A solar panel?

    Hii Everyone, I want to make a project in which I want to charge my 12V--7.2Ah SMF(Sealed Maintenance Free ) Battery. I have a solar panel which has Vmp of 18V , Isc of 0.75A and rated power of 12W. I personally think that this solar panel is generating much more power than to charge the...
  2. Rahulk70

    How to determine the state of charge of a NiCD battery when charged via a Bench PSU?

    I’ve a bunch of Sanyo Cadnica cells of various capacities in my possession. Though they are a bit old they have never been used and are NOS. I’m currently trying to charge a KR-FH 7000mAh cell. As per the label on the battery(please see picture below) it says at 700mA it should be charged 14-16...
  3. J

    Homemade Power Supply How to?

    I'm posting today hoping for some guidance on a project i would like to attempt. I recently came into a lot of 64 12v 7AH Sealed Lead Acid batteries from a backup UPS. The batteries are still good and take a charge and load like normal for the most part. Since i only have the batteries and...
  4. A

    Li-Ion battery current limitation??

    Hello all, I am using TPS61253 Boost IC to boost 3.8V from 375mAH Li-Ion battery to operate a load of 2A and also charge the backup Li-Ion battery of 115mAH using BQ25895 chip. Looks like battery is not able to deliver the necessary current and the load circuit does not boot up correctly. Is...
  5. E

    how to properly make a charging circuit -- 2s 7.4V to 5V 2A

    I have 2 18650 li-ion cells, each at 3.7v (in case you don't see the pictures, they are available here : ) and this bay with this white connector I saw on youtube that depending on the length of the cell, we can know whether they have...
  6. johnnybaloney

    Fried Sony BCG-34HRE NiMH battery charger teardown

    Hi, My Sony BCG-34HRE battery charger has just died with a loud buzz and then a pop, so I decided to take it apart and see what exploded inside. Getting inside required a bit of wrestling (damn you hidden screw!) and I took a few pics which I'm sharing here for posterity. There...
  7. Amir Mohammad Soltanpour

    Variable Current Lead Acide Battery Charger

    Digitally controlling charge voltage with some regulator like Lm317 is a matter of using some resistor and transistor as stated in lm317 datasheet to select from multiple pre defined voltage. But what about choosing output current ? How it can be adjust with digital signals from...
  8. O

    battery charger not happy with a long wire connection

    I have a Chinese battery charging control module (XH-M603) that I'm trying to use as a float charger for a 12v SLA battery. The problem is that the module only works correctly when it is connected close to the battery using short leads. When I connect the module using 30ft of wire (which is how...
  9. D

    Question about charging two 18650 batteries

    Hello! First time ever posting to a forum of any kind. I have a charger made for charging a single 3.7 volt Li-Ion battery or more than one cell could be charged but at a slower charge rate. My question is there anyway to charge the two cells ran in series as the picture I attached shows with...
  10. M

    Battery charger and MPPT controller

    I am working on a project where i have to charge a battery from a PV panel source. I have a boost cascaded by a buck converter for my system. The boost converter for P&O MPPT and the buck for the 3 stage battery charging algorithm. So now I am looking to implement the control. So on a...
  11. D

    Keep running circuit while solar charging

    Hi All, I would like to build a simple automatic irrigation system with Raspberry Pi zero, the thing is that I don't have access to electricity outside. I thought to connect 5v solar panel + 3\4 chargeable batteries. Im not that familiar with building control circuits for charging batteries...
  12. 3

    Solar charger & timer

    Hi I need help building the electronics for a home project. Essentially I am trying to: 1. Charge a battery with a solar panel 2. Activate a 12solenoid valve controlling pressurized water with a push button 3. Have the solenoid close after an adjustable time delay I was able to find solar...
  13. vmazsit

    Making a lamp portable with 18650

    Hey! I have a lamp which is powered by a 5V power supply and I want to upgrade it by powering it with a battery pack. The issue is I want to use the lamp while charging its batteries but as I know charging and draining at one time is impossible so I searched for simple switching circuit but I...
  14. I

    Head Light Bulb Kit and Li-Ion Battery Pack

    Hello, I have lithium-ion battery pack that consists of 21 cells( 3 parallel,7 series,one of them 4,2V 3.4Ah). I use this battery pack with BQ7791504PW from Texas Instruments for battery protection.This IC achieves pack protection via CHG and DSG low-side NMOS FET drivers. I use this battery...
  15. Nikolas_

    Battery charger circuit design

    Hey, so I am trying to design and build my own battery charger for 4 cell LiPos (including HV-LiPos with 4.35v/cell) but I don't have a lot of experience with circuit design. I designed this circuit so that it can either supply a constant voltage or constant current to the battery with the...
  16. Rahulk70

    Fast acting device to protect a high current 6/12V charger during short circuit?

    Hello, Which device best protects the rectifier and electronics inside an older style car battery charger? I have seen some manufacturers use an ATC blade fuse but I'm not sure if that will act fast enough to protect the circuits. I came across another device too, it's a Bussmann Circuit...
  17. jhon15

    How to calculate Rt1 and Rt2 of the MCP73833 IC ?

    I'm developing a battery charger with the MCP73833 IC. I want to set up the charge temperature window between 0 °C - 60 °C . How can I calculate Rt1 and Rt2 ? The equation: The datasheet: Datasheet
  18. A

    Circuit board help

    I have a wireless keyboard case for my iPad mini. When it’s off and I put it to charge the charge light turns on. But when I turn on the keyboard it’s dead. I’m looking at the circuit board and I think it has to do with the battery. The board looks fine. Can someone help me ?
  19. P

    Li-ion battery charging termination current

    Hi all, I have a question about Li-ion rechargable batteries. I have almost no experience with it. Documentation to battery is very poor, but there is an info about charging profile: Stage 1: Constant Current 0.82 Ampere (0.2C) until Voltage reach 4.2V Stage 2: Constant Voltage (4.2V) with...
  20. T

    Building a charging circuit for a 2 cell Li-ion battery

    Hi, I am in the process of designing a battery to use with a pair of FPV goggles for drone racing, the goggles require a 2 cell battery, but I don't have a 2 cell battery charger. I do have a bunch of TP4056 charging boards, and I was looking to design an all in one unit that would hold 2...