The SparkFun Battery Babysitter is an all-in-one single-cell Lithium Polymer (LiPo) battery manager. It’s half battery charger, half battery monitor, and all you’ll ever need to keep your battery-powered project running safely and extensively.
The Battery Babysitter features a pair of Texas Instruments LiPo-management ICs: a BQ24075 battery charger and a BQ27441-G1A fuel gauge. The charger supports adjustable charge rates of up to 1.5A, as well as USB-compliant 100mA and 500mA options. It also features power-path management, guaranteeing power to your project even if the battery has died. The self-calibrating, I2C-based BQ27441-G1A measures your battery’s voltage to estimate its charge percentage and remaining capacity. It’s also hooked up to a current-sensing resistor, which allows it to measure current and power! It’s a handy IC to have, if you ever need to keep an extra eye on your project’s power draw.
This skill defines how difficult the soldering is on a particular product. It might be a couple simple solder joints, or require special reflow tools.
Skill Level: Noob - Some basic soldering is required, but it is limited to a just a few pins, basic through-hole soldering, and couple (if any) polarized components. A basic soldering iron is all you should need.
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If a board needs code or communicates somehow, you're going to need to know how to program or interface with it. The programming skill is all about communication and code.
Skill Level: Rookie - You will need a better fundamental understand of what code is, and how it works. You will be using beginner-level software and development tools like Arduino. You will be dealing directly with code, but numerous examples and libraries are available. Sensors or shields will communicate with serial or TTL.
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If it requires power, you need to know how much, what all the pins do, and how to hook it up. You may need to reference datasheets, schematics, and know the ins and outs of electronics.
Skill Level: Rookie - You may be required to know a bit more about the component, such as orientation, or how to hook it up, in addition to power requirements. You will need to understand polarized components.
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Based on 9 ratings:
2 of 2 found this helpful:
Would be nice if it included a step-up DC/DC to provide a constant 5V output, like the "SparkFun LiPo Charger/Booster - 5V/1A", while retaining the coulomb counter/fuel gauge - especially for the price.
My main concern is that the copper pour on the bottom of the PCB around the charging IC is very small, so that spots gets rather hot when charging at 1.5A from a 5V source. This should've been a 4 layer board with a solid copper pour on the bottom side and lots of vias to conduct that heat away.
In any case, the coulomb counter is very useful to minimize power consumption in a battery powered project.
P.S. - The hookup guide claims the default charge rate is 1500mA - it appears to be 100mA.
Thanks for the feedback and review. In terms of the charge rate listed in the hookup guide, you are correct. By default, the switches should be in the ON position from the supplier which would set it at 100mA. Our production does not adjust the switch under the test procedures since it is under the pick-n-place yellow film.
I verified it against the boards on storefront and checked the schematic. The tables (for the “Charge Rate” and “Power Path Operation Modes”) and associated paragraphs in the tutorial have been adjusted to reflect this information.
1 of 1 found this helpful:
But looking for documentation; beyond that, the build quality is excellent on the rash of products I just ordered! Arrived exactly on time!
The big thing I wish I had gotten was a list of practical connectors that pair with the board. I need to find connectors to solder onto my battery terminals, etc.
Very much looking forward to plugging this into my setup once I find the de-facto documentation.
1 of 2 found this helpful:
Be warned: the documentation says they are using a BQ24075. If that were true, according to TI's docs, it would have 5.5v regulated output, not this funky battery-dependent voltage. I bought this specifically because it had this feature, but it doesn't. I've made a couple of attempts to contact Sparkfun for clarification, but have been effectively ignored at this point.
ALSO: If you try to use this on a device that doesn't already have a library for interfacing with the BQ27441-G1A over I2C, GOOD LUCK. TI's documentation on this is difficult to understand at best.
I can positively verify that there is a BQ24075 IC on the Battery Babysitter. The full part number for the IC on the board is BQ24075RGTR and we get them in reels directly from a well know and respected TI parts distributor. It's possible that our design doesn't allow for a 5.5 volt output, but I can say for a fact that there is a genuine BQ24075 IC from TI on this board.
Unfortunately I can't locate any messages or queries from you about this part. Are you sure you sent them to us? If we didn't get a request we wouldn't have responded to you. This could be why you feel we are ignoring you. I would encourage you to reach out to us on our forum if you have more questions and we will do our best to answer those there.
Battery voltage measurement resolution is great at 3 decimal places to the right. Current and Power measurement are also great with polarity and 5 digits of resolution. Battery Temperature measurement doesn't seem to be reading anything that I can tell. Tried different wiring on TS terminals and cut the jumper. Nothing changed the almost static reading 4 digits. Timers are another feature that didn't seem to follow what the data sheet says. Charge current was always MAX. Never saw Preconditioning occur. SOC is another area that behaves oddly. Never really know what the "real" state of the battery is with numbers shown. It appears to work best when connecting a "rested" battery and then monitor the discharge profile. When connecting a charger the SOC number immediately changes to something different. Makes one wonder what the state of charge really is. There are nice things about this device such as the values returned from the monitor chip are signed or unsigned 16-bit integers, which makes converting to BCD digits for a character display very easy. The 1.5 amp charger capacity is nice instead of being limited to 500 milliamps. I missed having a JST header on Vout port and QWIIC header would have been nice to have too. There is a lot to like about the very stable voltage, current and power readings this device displays with a lot of good resolution too, many digits. But the quirks that I have pointed out just take away from any confidence in using this device in a serious LiIon or LiPo project.
Work realy fine. Exemple code work well to and permit and quick use.
I’ve connected this thing to Raspberry Pi. Linux kernel already supports it.
Proper device name that I’ve used is bq27441
Great documentation and videos. Very well thought through. Easy to hack as well.
This will serve as the cornerstone of my battery based projects