diymore Li-ion Battery V3 Shield 1 Holder 3V/1A 5V/2A USB Power Bank Battery Charging Module 1865O Battery Holder

If you're looking for a reliable and versatile battery holder for your electronics projects, the diymore 18650 Battery Holder Double Li-ion V8 Battery Shield Micro USB is an excellent choice.Upon receiving the product, I was impressed with its sturdy construction and easy-to-use design. The holder is compatible with two 18650 batteries and features a micro USB port for convenient charging. The V8 battery shield also ensures that the batteries are protected from overcharging and short-circuiting.One of the standout features of the diymore 18650 Battery Holder is its versatility. It can be used with a variety of electronics projects, including the Raspberry Pi, Arduino, and other microcontrollers. The holder's compact size also makes it ideal for portable projects that require reliable and long-lasting power.In addition to its versatility, the holder also boasts excellent battery life. When fully charged, the 18650 batteries can provide hours of uninterrupted power, making it an ideal choice for projects that require consistent and reliable power.One potential downside is that the holder may not be compatible with all battery types, so be sure to check the specifications before purchasing. Additionally, the holder may not be suitable for high-current applications, as the batteries may not be able to provide enough power.Overall, I would highly recommend the diymore 18650 Battery Holder Double Li-ion V8 Battery Shield Micro USB to anyone in need of a reliable and versatile battery holder for their electronics projects. Its sturdy construction, easy-to-use design, and excellent battery life make it a top-performing and reliable choice for a variety of applications.

I'm mostly writing this review to document the date of which I put this into operation. When I received it, I tested it when I received it and it worked that one time fine, it powered my wireless iPhone charger. I did have it in my possession for about a week before I installed it into my 3d printed part at which time it did not work. All 3v and 5v connectors on the board shows 2.2 volts. Batteries are full, and tested four different charged batteries. The connectors to the USB-C connector shows 0 volts. I'm buying another one in case it was me that damaged it electronically, but if the new one doesn't actually work, I will be returning both.

Here's the good:The DC/DC converters are very efficient, both the 5V and 3.3V - like 94-95% across the whole range of input voltages that a battery is likely to generate. This is WAY better than a lot of DC/DC boost converters you can buy out there.Here's the 'meh':There are a set of LEDs on the bottom. For low current, battery powered devices, this is wasteful and consumes power for no benefit. They are easy enough to remove once you have the device operating properly.The device does not automatically turn when a battery is inserted. You must press the "enable" button once to turn it on.Here's the bad:There is an auto-sense that detects when there is no power being consumed and shuts the unit off. The definition of "no power being consumed" means less than 90mA, which is really quite a lot if you are using this device for a low-power microcontroller design. After about 30 to 35 seconds of "no-load" (<90mA) the unit will shut itself off.They provided a switch to "disable" the auto-sense, but this works by placing a fixed 90mA load on the unit to insure that there is always load above the shutoff threshold. For a long-lived battery device this is unacceptable as 90mA is more than my target design consumes and would drain the battery very quickly. This is a very poor, inefficient solution to the problem and not very good engineering.There is a solution to this, but it is a little hacky and requires cooperation with your target device. I added an external circuit (a single 2N7000 and a control line) to emulate a button press on the "enable" button every 20 seconds or so. When my system is running, I have to make sure that this circuit gets activated (pull the enable pin on the switch low for about a tenth of a second) every 20 seconds. This appears to reset the "no-load" timer and you get another 30-35 seconds. Do this every 20 seconds or so and the unit will run indefinitely at very light loads (my specific design consumes about 2mA nominally).You can't do it too fast as two quick presses of the enable button are what signals the device to shut off.I gave the unit 4 stars because the DC/DC converters are so darned efficient. If I had not been able to do the button-press emulation trick to keep the unit running under light load it would have gotten one star.I hope this helps anyone trying to use this DIYMORE battery shield for very low power designs. It you have the knowledge and provisions to tickle it appropriately it can work well, and be very efficient. If not, then the fixed load, or auto-shutoff might make it tricky to use effectively and efficiently.

This battery pack changed my outlook on battery banks. I originally bought this for a Raspberry Pi project but quickly realized that I've been paying high costs for battery banks just to get some slightly useful features. This has made it to where I can make a battery pack to my liking for size, capacity, and external ports. Not only does it come with a micro-usb and USB-C ports for input, but you have a USB-A for output and if you know how to solder, you have 4 connections for 3v and 4 connections for 5v that you can use to add more ports for output.It has a simple operation, fits a wide range of batteries, and is made of good quality materials for the board and the battery holder itself. I use it on my Pi project but also for charging random things and am planning to buy more to make my own battery pack for my ring doorbell, and want to look into the larger versions to start making my own battery banks.