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Alternate thought, why is the temperature so low? If possible bury the battery in the ground as much as possible, and use the higher temperature of the earth itself. The battery does not out-gas like lead-acid, so no explosive mixture. Trying to put the battery high up on a pole will be counterproductive from a charging point of view.


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I read the datasheet again for the TP4056 charger and it states No blocking diode is required due to the internal PMOSFET architecture and have prevent to negative Charge Current Circuit. I think this means that I don't need the diode I placed at all, and the internals of the chip should keep everything in line.


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Yes, the same kind of current-sensing based circuit is possible to be used, but it will be a bit harder to make it work, since the feedback loop of DC-DC converters is more finicky. Also, while the DC-DC converter improves efficiency, note that you still are wasting a ton of energy in the current sense resistor (the 1Ω your schematic). If you charge at 1A, ...


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Make sure that when you switch over, the battery is still in the circuit. Check that. You can't run the fridge with that battery and that trickle charger. It would work if you had a much larger battery, or a much larger charger, or much smaller fridge, but not with the equipment you have. When the fridge starts to turn on, it draws so much current that ...


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Small voltage difference is inconsequential for this kind of high power application. At least the power consumer should be aware of this difference, since all source parameters are clearly communicated to consumer over Power Delivery messaging protocol. The producer-consumer have an option to negotiate the best (optimal) power contract. If for some goofy ...


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There are charge cycles at different stages of battery state and temperature. If you choose the float voltage, this would be ok to charge and use.


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A battery is a lumped element, so it's either charging or discharging, not both. If your load is active, it might charge more slowly depending on the load and charger characteristics. However, that in itself won't harm the battery.


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A shunt resistor value is a trade-off between how many millivolts you can afford to lose, and how easy it is to measure the voltage. Common values for the voltage drop at the rated current are 50 mV or 100 mV. If you want 50 mV for 5 A, then the resistor would be 0.05V/5A = 0.01 ohms. If you can afford to lose a higher voltage, then it will be easier to ...


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Is it safe to continue charge Li-ion after 0.12A threshold till 0.082A Probably. The amount of extra charge put in between 0.12 A and 0.082 A should be very small. If you are worried about overcharging then lower the voltage to eg. 4.1 V instead of 4.2 V. This will slightly reduce capacity, but puts less stress on the battery than fully charging and ...


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Efficient depends on battery life and reliabilty. Version 1: charges the battery and the battery gives the power to the circuit. Zero transition time in case main power fails, cause load is always served from the battery. High strain on battery. Version 2: charges the battery but also gives power from main line to load. Battery also charges, but only when ...


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When no battery is connected the circuit operates as a constant-voltage source having an output voltage of \$\mathrm{V_o=11\cdot 1.25V = 13.75VDC}\$ with zero current flow. When a battery is connected, if the battery voltage is less than, say, 12V then the circuit will work as a constant-current source having a constant output current of \$\mathrm{I_o[A]=V_{...


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It would be helpful to have a data sheet of this battery, however bad it is. 0.2C charging appears excessively conservative. This would mean over 5 hours for a full charge (most likely 6-7 hours). I’m not familiar with every possible Lithium-Ion chemistry, but I hadn’t ever heard of a chemistry requiring only 0.2 C charging; note that it might be beneficial ...


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Congratulations on asking a good question that should have been covered by the instructor. The battery will be damaged or destroyed if left on charge when the battery is fully charged. A 1S LiIon cell must NEVER be charged to above 4.2V. It MUST NOT be floated at 4.2V It can be floated at 4.1V or less. 4.1V max still gives most of capacity, 4.0V is lower ...


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Texas instruments makes a chip BQ24392 that can detect if the host is a CDP, SDP, or DCP. I think the way to answer you question is to get the BQ24392EVM (or similar) and plug it into a bunch of computers and see how many of them support CDP (you will know if the indicator light comes on). https://www.digikey.com/products/en?keywords=BQ24392EVM I have ...


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So the question lies in how does the laptop switch from using AC wall power to using the battery, without shutting down for that split second when you unplug the machine from the wall power adapter? Short answer: very fast controls. There are many ways of implementing this functionality, but on modern (circa 2020) motherboards this is done by means of a ...


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The battery and power supply schematics for laptops are very complex. When the laptop is connected to the AC mains power supply, the voltage presented by that unit is provided to both the internal switching power supplies AND the internal battery charger unit. The battery will have FET switches or at minimum be diode isolated on the output so that a laptop ...


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That's easy. It's like your car. The laptop is always connected to the battery and can always draw from it. Meanwhile, the "alternator" (Power block in this case) is injecting power into the system. In your car, the alternator is tuned to output exactly the float voltage of your battery, so current flows in until it's fully charged, then battery ...


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A number of laptops work just as you describe, and it is in fact very rough on the batteries. Not only charging to 100%, but just sitting idle at 100%, stresses a lithium cell. Some charging systems divert input power separately to battery and load when plugged in. This is a better system, because it gives more control over the battery current (since it ...


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My "analog" Seiko Solar watch uses a rechargeable battery V157-0AA0 according to SEIKO website. Since there is no self-heating or high current, the wear factor is extremely low. You can see the conditions required for operation. Sor so many years, I have had a failure since receiving this birthday gift. The same with my SHarp solar calculator, many ...


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Take a tumbler filled with tap water and add a tablespoon of table salt and mix. Put in a couple forks, separated by a couple inches with a sponge or dishrag. Put that makeshift resistor in series with your LED and it won’t likely burn out. Don’t worry about getting it backwards, most LEDs can withstand quite a bit of reverse voltage.


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A voltmeter will well you which lead is what. Otherwise, sometimes the cord will have a small 'ridge' on the + side, but that's not for certain. An LED with a 1K or so load resistor in series can also work. But be warned that LEDs don't much like reverse polarity, you can protect it with a regular diode in parallel, wired in opposite polarity to the LED. A ...


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In theory it sounds feasible to me. If a 400mAh battery last two weeks, it means that the circuit consumes about 4.3mW on average (400mAh * 3.6V / (2 wks * 7 days * 24 hours)) . Let's say that your shake-based generator will work 30 minutes per day, then it would have to generate about 206mW when active (24 hours/ 0.5 hour * 4.3mW). On top of that I would ...


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Most likely voltage. Whenever a battery discharges its voltage reduces. If your phone's battery has a nominal of 3.7 volts this means that fully charged it will have 4.2V and fully discharged about 2.5V Now you can monitor the voltage and determine the percentage of charge with a simple formula like the following: (Current voltage - Discharged voltage) / (...


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Unlike the fuel tank of a car which has a simple physical parameter, the volume of fuel, a battery's voltage does not fall linearly with the amount of charge left in the battery. In fact a lot of effort goes into trying to make the battery voltage remain constant until it is close to fully discharged. Figure 1. A randomly chosen battery discharge curve. ...


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The internal resistance of the battery plays a larger role in the maximum current it can provide. Suppose you have the circuit shown below: The boxed area represents the battery and the resistor RL represents the load you are trying to power. Inside the battery, you have a voltage source and the internal resistance of the battery, which may be in the range ...


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Batteries has a parameter that is called "C rate". This parameter simply determines how much current It can give in time. If too much current is required from battery then It's chemistry is corrupted.


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If a batteries mA capacity is so low, that it can't even power the smallest loads without fully discharging immediately, then this could probably happen. Two scenarios where this could happen are when the battery is dead, so it can't keep a charge, or when you're using a small battery that isn't designed to have a large capacity. So pretty much at this point,...


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I conducted a simple experiment with a used 18650 Li-ion battery cell. The cell has no capacity label on it, which I guess it was originally between 1500mAh and 3000mAh. 1st Charge I started charging by setting the charge voltage to 4.2V, limiting the charge current to 0.5A with a lab power supply and observed the terminal voltage. When the terminal ...


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Is trickle charging property of the charger that I plug into the wall socket and connect to the phone? The phone chargers which we connect to the wall socket are AC to DC converters which provide 5 V. The trickle charging and other features are from the charger IC or section which will be put inside the mobile phones. After the battery drops to some ...


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It looks pretty similar to this, but no guarantees on the specs or anything. You said you measured no continuity, but the ones on that page range from 5K to 100K; maybe you weren't on a high enough range to see it. If this is what it is, they have a fairly low failure rate, at least from electrical stresses.


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Lastly remember the safety mantra "Volts can jolt but mills can kill" always endeavour to keep currents as low as possible, battery charging currents can be quite high 5-10 amps this can be normal..... use good wire here and proper connections. don't mix and match batteries and panels always try to have the same type and capacity per setup, if they are mixed ...


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Other points to remember Volts time Amps equals power, power in is always more than power out, due to loses, Led strips are polarity sensitive, plus to plus and negative to negative and are very low power usage. Battery boxes often have USB chargers built in. Remember you get what you pay for. A good mppt controller can cost around $100.... LED strips is ...


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There are a few issues here with your design that will cause you grief. Generally the output of the Solar panel will usually be more than your battery can handle, (depends on the make, model and number of panels used) I would look at using 12V AGM batteries connected to a MPPT Charge Controller to regulate and control the charging voltage and current to the ...


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Won't the current flowing from the capacitor damage the battery? Yes. To prevent damaging the battery you should use a proper li-ion charging circuit. Will using a resistor prevent the damage? Yes, if it is large enough to limit current to 5A (0.5C charge rate) or less. However using a resistor for this is quite inefficient, since it wastes 50% of the ...


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A battery stores energy. If you want to charge from another source, then that has to supply that amount of energy, plus a bit more for losses. How much energy does your power bank store? You say it's 10Ah. Unfortunately, you don't say at what voltage. Let's assume the manufacturer is trying to 'big up' their device, so we'll use the lowest plausible voltage ...


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I am using a Samsung A6 and I use all manner of chargers that are available to me at the time with no ill effects whatsoever so far.


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@diegogmx's hunch was right(check all the comments). The fault and charging pins cannot be directly connected to VIN, but a current limiting resistor must be used to connect them. I was in touch with Analog devices Engineering support, and they cleared my doubts. Thank's for the help everyone.


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Surely the phone tries to negotiate what kind of power supply there is, and then it will draw only standard amount of current if there is no fancy high current charger present.


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Firstly you need to PRACTICE caution when using a lithium ion battery. Using words like I think does not go well in terms of safety. Always assume there's no protection circuits. Only move to the next question if the answer is yes. Secondly check your battery voltage, is it above 2.4V? Third, remove the load and battery test the output from the B+ and B- ...


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