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MOSFETs only block current in one direction. That's why the symbol contains that parasitic body diode. You have a short which may be unfixable without significantly more circuitry to support back-to-back NMOSFETs sharing a source connection so current in both directions is blocked. Just using a step up converter and series cells or step down converter and ...


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Is it possible this is a health or exercise band? In which case these might be skin contact tabs that measure skin resistance. From your picture there also seems to be an optical input for possible blood flow/pulse rate detection, etc. If there is a usb connection is it possible this is the charging method, or there could be a wireless inductive charger ...


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Two PIN charging port, connected to charging cradle through clip. They use magnetic holders to make contact with 2 pins and often a cradle needs to keep it on side or raised so the strap or cable forces do not separate the magnetic holders to permit contact with pads.


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Since you have 6 Li-Ion batteries in series, you could charge them at 25.2V (Since the max charge for a Li-Ion is 4.2V * 6 = 25.2V). The current used the charge the cells depends on the battery itself. Batteries usually have a part number printed on them. So if you find the datasheet, then you can determine the maximum current you can charge the batteries at....


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Well, let's see..... The solar cell has a curve of voltage versus current. The specification of 5v/1A is for a specific load point, for a specific angle to the sun and for a specific geographic latitude and for a specific time of year. If your battery pack is a 5 volt pack, your will NOT draw much current of it is fully charged or close to fully charged. ...


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Yes, you can totally replace the battery, given that it has the same dimensions, number of wires, and matches the current & voltage of the original one.


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Please confirm. You have 2 x 10S6P LiIon batteries. 2 x 42V MAX chargers designed for use as 6S LiIon chargers. Note - these CANNOT be "36V chargers". 10S = 36V AVERAGE but 4.2V x 10 = 42V charged. You also say 44 Volt. 44V = 4.4V/cell is damagingly high for most LiIon. Chargers MUST suit battery. Can you provide brand and model for chargers and ...


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Yes, It should work fine to put them in parallel if we assume the BMS's on each are not doing anything out of the ordinary. If you want to be extra cautious you could charge them separately.


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You could make a custom charger BUT I'd strongly recommend against it. The energy difference between 4.2 & 4.4V will be small and you will get useful whole of life capacity improvement by using 4.2V end of charge. You can test this by CAREFULLY manually charging to 4.4V with a power supply set to 4.4V and current limited to Imax, then letting the ...


2

What you are attempting is dangerous practice. There are many different types of 18650 cells with different chemistries for differnet intended purposes. A battery must be built with cells of matched characteristics; internal resistance, charge retention, charge and discharge capabilities etc. Mixing different makes of cells within a battery is almost certain ...


2

50Hz is really low audio frequency. High pitch noise (above 10kHz usually) is coming from cheap switching power supplies. Normally designers try to use higher frequencies (outside audio range) to avoid this annoyance or mechanically dampen it (e.g. gluing), but cheap supply designers... well, don't care. Here is wiki article about it. As for lifespan - any ...


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