Smbus Li-ion Battery Charger Schematic
BatterySpace Smart Battery System (SBS) boards are designed to monitor & manage 7.4V / 11.1V / 14.8V Li-Ion battery packs. (Please tell us what capacity do you use when you place an order). With SMBus Interface, you can set up protection parameters and to collect battery data through the SMbus V1.1 protocol right from the SBS.
- All these things are assembled on TP4056 Li-ion battery charger breakout board whose link is mentioned in step No-2. We need to do only two things, give a voltage in the range of 4.0 to 8.0 V at input terminals and connect a battery at B+ and B- terminals of TP4056. Next, we will build our rest of the battery charger circuitry.
- This is a Lithium-ion charger for lipo batteries. Circuit schematic shows configuration for charging single 3.7V lipo battery but voltage can be set to charge several batteries in series. Lipo charger sets a current limit with the LM317, and 1 resistor, and the voltage limit with the TL431, and 2 resistors. 1K resistor is needed to let the TL431 decrease the LM317 current, and to provide the.
I have a 3 cell Li-Ion battery connected in series and want to charge them with a single battery charger IC. What I found is BQ24105, a Stand-Alone Battery Charger with following schematic for charging 2 cell battery.
- Does this battery charger IC, handle cell balancing?
- Is cell balancing required, I ask this because this IC claim to charge multicell battery, but dont seems to handle cell balancing
2 Answers
$begingroup$The BQ24105 can handle multicell battery charging as stated in the datasheet. The IC just takes care of the charging of the batteries but assumes that the battery pack (the dashed box in Figure. 1) has all the necessary protection circuit.
Polaroid Li-ion Battery Charger
A battery pack with multiple batteries in series should have a protection circuit that monitors battery voltage, temperature and current. A balancing circuit is also necessary to monitor each cell in the pack to equalize the voltage for all cells.
Even if you buy the same type of batteries from a single manufacturer, each cell has small variations causing them to charge and discharge differently which makes it necessary to have a balancing circuit.
Daniel
$endgroup$Battery Charger 3.7 Li Ion
Universal Li Ion Battery Charger
$begingroup$BQ24105 will not handle cell balancing, But it should be take cared as suggested by Oskar Persson Answer. Note that battery balancing can be implimented passively or using active components.
Fortunately in a system with a fully integrated battery charger(like in my case), circuit comes with a Battery Fuel Gauge IC like BQ40Z50-R2 to measure state of charge(SoC) in the battery pack.
This seems a miracle to me, as these Fuel Gauge IC comes with an integrated battary balancer. So as long as you have a Battery Fuel Gauge in your system, that thing will handle cells balancing for you.