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@allObjects
For quite some time I wanted to control the charging and discharging of battery/ies of stationary and mobile photovoltaic system to gain some insight. Most recent I looked into the Maxim MAX17261, which is even better than a good coulomb counter, and coulomb counters already deliver pretty good information about the charge state.
For a long time I was looking for measuring on the hight side, and there are sensors that can measure current on the hight side. With the prevalence of LiIon. and LiFePO4 - which need a much tighter control to prevent meltdowns and explosions and discharge and charge - any device includes full control and protections regarding voltage and current with sensing on the low-side. Will see how far I'll get when done. Attached schema shows the battery pack and sensor part. The powering of and from Pixl.js is not drawn yet... but I'm thinking of a simple 5V buck DC DC converter, because that will also drive the PWM driven Micro Fan to have active temperature control.
For a cheap pre-solution for both charging and discharging for a 24V medical device from a 12.8V 10Ah LiFePO protected battery pack, I use a readily available smart buck/boost DC-DC converter. For the currents I need it works perfect (after making the thermal contact better and - planned increase the size of the heatsink for higher charge current.
The device is a DC-DC 5V 12V 24V Step Up Down Power Supply CVCC Adjustable Converter LCD Display - for example at https://www.ebay.com/itm/DC-DC-5V-12V-24V-Step-Up-Down-Power-Supply-CVCC-Adjustable-Converter-LCD-Display/164345548755 .
Unfortunately, it is only manually programmable - afaik- and not mc programmable over some serial or i2c / spc connection. But nice is the ConstantCurrent (CC) function for bulk charging and ConstantVoltage (CV) for balancing / finishing, all without intervention. What I have not tested yet is feeding the charging from a solar panel. So far I used a plain power supply for (stationary) charing and testing. With the MAX17261 circuitry I want to validate its accuracy.
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