Electronic load for charging/testing small batteries - Page 1
Forum section: electronics / testgear

author: RiRaRi
author_rank: Regular Contributor
timestamp: April 14, 2024, 03:15:58 pm
content: I test a lot of older camera batteries. The biggest ones are 8V 2A Li-ion ones. But most of them are much smaller found in compact cameras. I need load which could charge and discharge/test capacity as fast as possible. I want decent device but accuracy is not very important to me. What to get? Thanks everyone for help.

author: macboy
author_rank: Super Contributor
timestamp: April 14, 2024, 03:49:40 pm
content: I would use a charger for RC such as the ToolkitRC M6, or any of many similar devices. The M6 can charge and discharge with balancing for multi-cell batteries, at up to 10 A. High rate discharge is accomplished by using an external load resistor, or if you use a big lead-acid (car) battery as the power source, it will dump the energy back into that battery. For a small compact camera battery, you would not need either type of external load, the charger can internally dump up to 10 W (that's nearly 3 A for a one-cell battery). This type of charger is very versatile, it can be set up for any type of lithium chemistry (Li-ion, LiPo, LiFe, etc.) or NiMH, NiCd, or Pb. They can cycle the battery several times, and track the capacity each time, so you can see if the battery is benefitting from cycling. Generally, it is safe to charge and discharge at "1C" rate, which means the 1 mA per 1 mAH capacity (so 600 mA charge or discharge current for a 600 mAH capacity battery). So a charge/discharge cycle will take about 2+ hours. You can't really rush it faster than that, not all batteries can be safely charged any faster. Don't forget that after discharging, you need to also do a storage charge, to bring the cell back to about 60% or so, in order to safely store it for a long time (storage completely empty or full WILL damage a Lithium battery).

author: Kean
author_rank: Unknown
timestamp: April 14, 2024, 03:50:46 pm
content: There are many options, but note that most general purpose electronic loads do not support charging unless it is specifically a battery capacity tester.One battery capacity tester that I use is the ZKETECH EBC-A05+. I've had a couple of these for about 8 years (originally bought on ebay), and they perform reasonably well for smaller battery packs. They can be used on a wide range of batteries, unlike some other testers which are intended just for single 18650 cell testing. The ZKE computer interface isn't great, but I rarely use that.In terms of testing as fast as possible, you are limited by the max charge and discharge currents of the battery (and the tester obviously). Note that testing at higher currents for faster tests will not be indicative of the battery in actual usage, but it can help with determining battery performance. Do not exceed the safe charge/discharge specifications for the battery. With an old battery, I'd always start of with a gentle charge/discharge/charge cycle.Another really useful tool for checking older batteries is a battery impedance meter. Check out the YR1035+. This will allow you to measure the internal resistance, which will increase with age and affect usable battery capacity.

author: RiRaRi
author_rank: Regular Contributor
timestamp: April 14, 2024, 05:10:09 pm
content: I got some good answers here, thank you. But to sum it up: what is best device for my job? It does not have to be electronic load but best device to check capacity and possibly charge the battery? Thanks

author: helius
author_rank: Super Contributor
timestamp: April 14, 2024, 06:41:26 pm
content: I'm fond of the charger-analyzers from SkyRC. The MC3000 is very flexible for all single-cell cylindrical batteries, and they have a range of units that charge and analyze multiple-cell packs, most named "B6" or variations thereon.

author: nctnico
author_rank: Super Contributor
timestamp: April 14, 2024, 08:30:14 pm
content: Quote from: RiRaRi on April 14, 2024, 05:10:09 pmI recommend not to try and charge discharge batteries as fast as possible but I'd try to stay below charging and discharging rates of 0.5C . This will cause least wear on the batteries.

author: sam_sam_sam
author_rank: Contributor
timestamp: May 13, 2024, 11:44:19 am
content: Quote from: helius on April 14, 2024, 06:41:26 pmThis is a nice battery tester when it worksIt has a couple of issues one is that Bluetooth module board is not the best quality and fails with little or no warning at allThe programming charging/discharging cycle is a little bit challenging you have to pay attention to how you set up this applicationThe one nice feature is the ability to turn off the charging/discharging cycles if you exceed the temperature limit but only if you programmed it in manually it is not by default also this feature is not available in the single mode charging or discharging modeThe SKYRC b6 is also a very nice battery testing machine but there a couple of things that you need to be aware of one you can use it in non balancing mode but you need to update the firmware if you have an older version of this device and can not be a clone version it does not have this featureIt has a temperature sensor that controls the cutoff point but you have to purchase the temperature sensor and you have adjust the temperature cutoff point because the default temperature setting is to high for me personallyOne note about using the balancing function on this battery testing machine is that if firmware has it or you have updated it and you have it set to unbalanced mode and you hook up the balancing plug and you have not changed the settings back to balancing mode it will give you an connection error but it does not tell you what it

author: RoGeorge
author_rank: Super Contributor
timestamp: May 13, 2024, 02:14:56 pm
content: Do you have a CV-CC lab power supply, and some LEDs?With this trick:https://www.eevblog.com/forum/projects/cc-cv-power-supply-as-a-contolled-load-for-batteries-(i-e-rigol-dp832)/any lab power supply can be used as a constant currentload, which also auto-disconnects the battery when the voltage drops under a certain value you can set from the power supply.

author: Njk
author_rank: Frequent Contributor
timestamp: May 13, 2024, 02:36:30 pm
content: An electronic load seems overkill for the task. What you need is an advanced charger with discharging capability. Some time ago, HKJ made a great gob by reviewing many of such devices.https://lygte-info.dk/info/roundCellChargerIndex%20UK.html

author: RoGeorge
author_rank: Super Contributor
timestamp: May 13, 2024, 02:53:29 pm
content: Also this, the VeryLazyLogger (a battery in parallel with a discharging resistor or LED, while the battery powers an electromechanical clock that will memorize the stop hour):https://www.eevblog.com/forum/projects/verylazylogger-(measure-usb-powerbank-capacity)/

author: mawyatt
author_rank: Super Contributor
timestamp: May 13, 2024, 03:29:51 pm
content: That worksBest,

author: thm_w
author_rank: Super Contributor
timestamp: May 13, 2024, 10:35:47 pm
content: Quote from: Njk on May 13, 2024, 02:36:30 pmYes those are great but they are all single cell 4V and OP is looking for 8V, which makes it much less common.

author: JohnC
author_rank: Contributor
timestamp: May 20, 2024, 03:34:28 am
content: You can perform reliable and accurate load tests using a simple USB Tester and a USB electronic load. Just need a Tester that has logging. Almost all modern Testers can cope with 15V-20V, and even the cheapest Loads (TIP transistor based) can cope with 13V, the majority now days can do at least 20V (for USB-C PD).As for charging, just use the original charger that came with the camera.For quick logging and testing, the ZB-206+ is the best cheapy battery tester (max load about 2.6A). Does 4-wire, load only steps by 100mA, but that's good enough. Like almost all Battery testers, it doesn't charge... that's the request that makes this topic almost impossible to answer.

author: CaptainBucko
author_rank: Regular Contributor
timestamp: May 20, 2024, 05:48:22 am
content: A single module of the DL24MP or similar can do everything you want with discharge and logging, plus will be more universal for other battery tests. I have several of them from AliExpress.

author: rs38
author_rank: Contributor
timestamp: July 28, 2025, 06:13:19 am
content: I tried the forum seach function a lot but how comes I do not find a single post mention one of those:https://www.owon.com.hk/list_dc_electronics_load

author: thm_w
author_rank: Super Contributor
timestamp: July 29, 2025, 12:06:16 am
content: Quote from: rs38 on July 28, 2025, 06:13:19 amYou are right no thread exists that I see either. I'll create a new thread instead, as its not applicable to this topic: "couldchargeand discharge/test capacity as fast as possible"New post:https://www.eevblog.com/forum/testgear/owon-electronic-loads-oel8511-200-500w-oel1515-150-300w/

author: Smokey
author_rank: Super Contributor
timestamp: July 29, 2025, 04:07:56 am
content: Get a 2 quadrant power supply. Lots out there. Often labeled as "mobile device" supplies.

author: nukie
author_rank: Frequent Contributor
timestamp: August 04, 2025, 05:53:35 am
content: Just get a RC charger/analyser they have selectable battery chemistry, number of cells and balancing taps. You only need to rig up your jig for your battery packs.