Questions tagged [lead-acid]
A very common chemistry system (lead and sulfuric acid) used in rechargeable batteries with a nominal cell voltage of 2.1 V. These batteries are used in automotive and robotics environments.
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Uneven voltage in series-connected AGM battery storage system
I've been working with a 48V storage system composed of 4 AGM batteries 250 Ah connected in series, all new from factory. The charger stops charging at 2.45V per cell, with an output voltage of 58....
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Can this battery be charged?
I have a battery that looks like a lead acid battery, contains lead, and it's from one of those little electric cars that kids can ride on, so it should be chargeable, but it says on the casing not to ...
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2 xLM324N lead battery charger fail. Images added
i have a Lead Acid battery charger that was given to me since its not working.
I have no 12volts output neither any led on.
Schematics do not appear after hours of google search
So far ive tested ...
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Using 2-cell lead-acid battery as direct replacement for single-cell lithium-ion battery
I've designed a system that remotely logs some data (position, some weather data, etc.) in remote areas that currently uses a single lithium-ion battery (~850mAh) that is recharged via a solar panel ...
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Lead-Acid battery charge voltage-current curve
I'm getting ready for winter in Ukraine, and want to extend the autonomous time of my existing setup consisting of UPS with external 100 Ah lead battery. I need at least 20 hours battery operation for ...
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Charging lead acid battery with DC motor
I want to charge a 12v lead acid battery with a dc motor used on the Power Core E100 rated at 24v 100w. I’m spinning the motor with a bike so the output voltage fluctuates which I assume isn’t good ...
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CV state lead-acid battery charge from solar panel
I simulate the charging of a lead-acid battery, using MPPT algorithms, Buck converter, a PID regulator and a solar panel. In the CC stage everything is perfect. The battery is charged up to 14.4V, so ...
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PWM Charge Controllers: Common types and example schematics?
I started on this quest because I needed to connect my programmable supply (KD3005P) 30V-5A to the PV input of a Landstar 1024B PWM Charge controller to test out the charging functionality of the ...
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Overvoltage Clamping protection for Boost Converter
I think my circuit is failing because of ESD and/or transients when initially connecting my device to a supply. How should I go about protecting the gate of M1? What's the best way to clamp the ...
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Using capacitor bank in parallel with lead acid battery
I saw some DIY projects about boosting car lead acid batteries. A supercapacitor bank is connected in parallel with a lead acid battery to stabilize the supply.
However, in the market, I can only find ...
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AGM battery maximum charge rate
I am trying to calculate the maximum charge rate of my AGM powersafe batteries 12 V 170 Ah, the data sheet says it's "0.5c¹⁰ amps"
I think 0.5 C makes 85 A, but not sure about the 10 to the ...
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I need suggestions/feedback on my simple active balancer schematics for two 12V batteries in series
Since I currently use a 24V battery system for my house using 16 12V car batteries (2 parallel banks of 8 in series with each other) and use the lower 12V side for additional devices, (as well as due ...
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How to use a BLDC motor, solar panels and batteries efficiently [closed]
I have a 48V 1800W BLDC motor, 4X 12V lead acid batteries and 4X 100W 12V solar panel.
My question is, can we use those 4 lead acid batteries when connected in series to power the BLDC motor?
If the ...
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Can two 12V batteries of different capacities be charged in parallel without damage?
I have a small 55 Ah AGM deep cycle battery and a larger 120 Ah AGM deep cycle battery in my car.
I know that wiring them in parallel to power a load is a bad idea.
What about connecting them in ...
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Need help validating my lead-acid car battery charger experiment
After experimenting and testing each block separately, I want to give it a try all together, however I have a few doubts. This is a car battery charger I'm experimenting with, for acid/lead non sealed ...
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Is it safe to run an instant power supply (IPS) with a flooded lead acid tubular battery (12V, 100 AH) in a small flat/apartment? [closed]
I live in a place where blackouts and power outages occur every hour. For backup power for two lights and two ceiling fans, I want to buy an IPS that runs on a flooded tubular acid battery, but I ...
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Lead-acid batteries discharged too far
I have been working with two 12 V lead-acid batteries in series. Accidently, we kept them turned on for a day or two and one of them drained to ~3 V and the other to ~8 V.
I immediately charged them, ...
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What happens when a CC/CV charger fails to give the required output voltage during CV charging and instead provides a lower constant voltage?
Lets say that I have a CC/CV charger based on buck topology and it is charging a 12V lead-acid battery through a solar panel. The lead acid-battery is being charged in CV (Constant Voltage) mode and ...
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Charging a lithium-ion battery using a lead-acid battery
I want to charge a lithium-ion battery using a lead-acid battery, but I want the two batteries to be isolated from each other. Is there any way to achieve this?
Edit: Both the batteries are rated for ...
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Lead-acid battery seems to be gaining capacity through use; why is this?
I am testing an alternative battery cartridge for an APC 3000 VA UPS. It's an OEM cartridge, but with the OEM batteries removed and replaced with Duracell 12 V, 5 Ah SLA batteries by a third party.
I ...
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How does the terminal voltage vs discharge time curve of an SLA battery change with time as the battery ages?
As a battery ages, it loses its ability to recharge back to its original capacity. How does this change the terminal voltage vs discharge time curve of an SLA battery? Since this curve represents the ...
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Why is the available capacity of an SLA battery and its cutoff voltage different for different discharge rates?
For example of this curve from this datasheet of an SLA battery:
For 0.05C discharge rate over a 20 hour period, the usable capacity of the battery is 1C. Whereas, for 0.09C discharge rate over a ...
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Why is is OK to use a relay to parallel lead-acid battery banks for charging?
I am currently faced with a British-built, Lloyd's offshore certified sailing yacht from 1998. Everything seems to be well-thought out and of the highest build quality. I am thus assuming that their ...
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I'm designing a three-stage battery charger for a sealed lead acid (SLA) battery. How will I decide which charging stage to apply to the SLA battery?
I am designing a three-stage battery charger for an SLA battery.
The three stages of charging I am referring to are: bulk (CC), absorption (CV) and float. (CC is constant current and CV is constant ...
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It is possible to overcharge a AGM battery at 13.7 V?
I have an AGM lead-acid battery, TED1251, which I want to use in a UPS. I bought it new. I put it in the circuit, where it is permanently connected to 13.7 V with a current limit of 1 A. The ...
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Protecting a battery charger from reverse polarity
I am building a battery charger for AGM (lead-acid) batteries that will output max. 5 amps to charge the battery, through a pair of clips. This makes it a possibility that the battery could ...
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What is the proper charging for worn-out forklift lead-acid batteries?
I know the standard way to cycle charge a battery: constant current at e.g. C/10 to C/4 until 2.40 V per cell, keep that constant voltage until it drops to about C/100. The hydrometer will show about ...
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Making a powerbank using lead-acid batteries [closed]
I have three 12 V, 12 Ah deep-cell lead-acid batteries wired in series that were used for a scooter. I’d like to repurpose this battery pack into a powerbank that can be used to charge electronic ...
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Simulation of a typical lead-acid battery for "serious game" purpose
I'm writing a game/simulation. The context of the game will be a sealed bunker with an environment control issue.
For this, I need a rough simulation of a typical industrial 12 V lead-acid battery:
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What is a safe max. discharge current for a tubular lead-acid battery?
I have 4 tubular C20 batteries, 225 Ah each (2 series-parallel-2 series) for a residential solar system.
I suppose the below is true:
C20 gives us the recommended current to obtain the advertised ...
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Lead-acid uninterruptible power supply safety [closed]
I use a UPS (Cyber Power, this one) that secures my PC from short blackouts.
It is located on the floor in my home office. When recently my kids were playing next to it, I started to ask myself if it'...
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Can I keep a 12 V lead-acid battery plugged in continuously?
I want to use the battery as a backup to a security camera that requires 9 VDC input. Can I keep the charger (12 V, 1 A or 14 V, 1.7 A) continuously plugged in to the battery and supply 9 V to the ...
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What is a "charge cycle" of a lead-acid battery?
I'm trying to develop an algorithm that would roughly estimate the health of a lead-acid battery tied to an inverter backup system.
It seems that my 200 Ah battery pack stays at 100% state of charge (...
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Can lead-acid batteries be stored by removing the liquid from them?
I have two lead-acid batteries of the plate type, 12 V/100 Ah each, used for an inverter.
I want to store these batteries for a year or two in a disconnected state.
A friend of mine told me it's ...
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Lead-acid battery screening options
We have a situation where we have on-hand many tens of thousands of 12 V lead-acid AGM batteries. The vendor had production issues, and we've found around 5-10% of these have an unacceptably low ...
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Can I charge a motorcycle / car battery with an external AGM battery, a step-up, a MOSFET, and one potentiometer?
I want to charge the 12 V battery of my vehicles (not EVs: car and motorbike), but my vehicles don't have access to the mains. I had the idea to charge the discharged battery (from now on called ...
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Durability of a battery
I have a device that consumes 10W and I have a 12V x 4.5Ah = 54Wh lead-acid battery, does that mean that my device can work continuously for 5.4 hours?
Does the same concept apply to lithium batteries?...
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Can I charge lead-acid batteries with more current than their rating?
I have a solar charge controller with these specs:
Type: PWM-Type Solar Charge Controller, 30A, 12V/24V
Battery type: DC 12V/24V (auto-detect)
Charge current: 30A
Discharge current: 30A
USB output: ...
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BMS with lead-acid battery pack
I assembled a lead-acid battery pack with six batteries. Is it possible to add a BMS for a lead-acid battery?
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Why is my lead acid battery suddenly dead?
I have a 12v 12ah sealed lead acid battery that was used 3 years in a battery friendly environment. Now I wanted to use it to power a security camera.
I use a cv cc buck converter as a charger. I ...
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What's the minimum float voltage to maintain a small lead-acid battery?
I wish to 'float' a Yuasa Y7-12 7 Ah, 12V sealed lead acid battery.
On Battery University it says that a voltage of 2.25-2.3 V per cell (so 13.5 - 13.8 V) will allow a lead-acid battery to regulate ...
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New deep cycle batteries produce low capacity and strange voltage behaviour
Batteries: Royal 1150k 105ah(20h)
Reserve capacity 180min(25A)
Inverter Load :27.5amp(constant)..measured.
My battery is lasting 30mins on this load.
When starting discharge from full it quickly drops ...
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How can a solar battery charger without separate load connection include three stage charging?
As you may know, there are several solar battery chargers (e.g. mppt Victronenergy ones) that only provide 2 connections, one to the battery and one to the solar panels. So, no separate load ...
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Resistive current sensor shows reading when I connect it in series with a battery while no current is flowing through it
I need to monitor the charge and discharge current of two 12V lead-acid batteries in series using an INA219 current sensor, and a 0.75 mOhm shunt. At first, I placed the current shunt in the low side ...
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Why do I hear hissing sounds when I discharge my sealed lead acid batteries at high currents?
I've been doing some discharge tests in order to figure out the Peukert exponents of two sealed lead acid batteries with capacities 7 and 9 Ah, in addition to an initial current of 2.1 and 2.7 A, ...
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12V boat lead acid battery suddenly failed
Battery on boat and powered by solar panels started acting really weird suddenly exactly a week ago. App shows voltage went from minimum 12.3V to min 6V in a day. On board voltmeter showing 11.9-12.2 ...
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Is battery charge efficiency related to its self-discharge?
I've read a couple of research papers and technical user manuals concerning SOC estimation, all of which mentioned both charge efficiency and Self-discharge but did not mention whether these effects ...
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DIY lead acid battery
I need a battery to act as capacitor for a small generator (~7V peak) which does not produce smooth DC. Normal capacitors are unable to deal with ~0.2 second dead time when load is attached, lithium ...
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Power camping lantern with 12v AGM battery
I have a 3 AA battery powered LED camping light/lantern. It draws (measured with a multimeter in series) about 18 mA when ON and 0 mA when OFF (ON/OFF controlled by a switch button).
It’s ON all night ...
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Can you use a 12V lead acid battery to switch a contactor?
So I'm making a manual precharge circuit for a solar car's motor controllers, and need to use a 12 V source to switch a contactor on/off thus switching between a resistive path and a short circuit ...
