This small review of how I tried to buyrechargeable battery type D (R20 / 373 / Mono / UM 1) instead of using expensive alkaline and weak adapters AA to D. Under the cut there are several photos, measurement + comparison, several figures and the total result for me personally - it is not worth it.
So I thought more than once that I do not likeI charge AA batteries in adapters to D every few months, for example, in beacons for Roomba, and then I bought a pump for fuels and lubricants that is powered by two D batteries and decided it wasn’t trying what the Chinese had on the market. The market was not a lot. The specified lot, which attracted attention with megapixels at 6000mAh and 9000mWh, and another, apparently original alternative to the specified product aliexpress.com/item/ZNTER-2-1-5-li-polyme-6000-USB-D/32893345190.htmlwhere the numbers are already only 6000mAh, and inproduct characteristics even somehow using the sly Chinese arithmetic indicated 6000mWh. Both sellers were written an offer to take an honest review of their products according to claim 18, since one of the desires was to look at the interior, and there was no desire to condemn what the blood was spent on, you know. As a result, one seller did not answer (with 9000mWh), and the second answered
Thanks for your inquiry
Of course you could purchase it if you like it
I hope that you will be satisfied with it
Please feel free to contact us if you have any problems
Best wishes Answer KO struck me to the depths of my soul, so that in order not to be biased, I decided to buy the specified kit from a silent seller, albeit at $ 6 more (what? And suddenly!)
Order came in 20 days by courier. Yesterday, I was impatiently unpacked, quickly captured the soap box-phone and set to recharge.
The weight of each is 50 grams. Charging refilled only 33 and 41 mAh. It was also measured the voltage on the batteries after installing one of them on the test 1.546V and 1.528V. Unfortunately, the ISDT T8 memory did not want to take this battery for a test, since the voltage above 1.4V was considered the limit of the acceptable for NiMh batteries (+ for some reason, it gave 2.1V to the battery, although it follows from the manual on the battery that it cannot be charged / recharged directly. It seemed that this was a bug in the charger, but connecting Turnigy LSD 2200mAh It was noticed that the voltage was 1.9V and when the discharge mode was activated, it successfully started from 1.4V, how much was the battery that was just removed from La Crosse BC-9009). In general, it didn’t work to test a freshly bought patient with a mega-brain charge, so he was uncovered not so businesslike, but a working iMax B6 with cheali charger v2 firmware. The discharge current is set to 600mAh, the lower voltage threshold is 0.9V, the lower threshold of the discharge current is 100mAh, the discharge capacity is 6000mAh and the discharge threshold is 120% of the capacity, I run Log View 2 and go to sleep.
I woke up in the morning, looking
Kicked KOCHERYZHKA! Well, I do not have clamps, and the window tape has come off the side, which was pressing the crocodile with the puck to the minus. Frowned, put on charging the first battery, connected the second one, having already twisted with the phone holder to hold the battery and press the contacts and launched everything in a new way. Note that the measurement stopped from losing contact after 5 hours 57 minutes 44 seconds of discharge.
So the second brother was again connected and running.in fact. I sit all this and hear the sound alarming! I look, and iMax beeps to me that they say the battery is disconnected again and 0.00V scares, I checked it with a tester, and really by zero. in a minute I look, again 1.5V! Clear. The board cuts off the power supply as soon as the battery discharges.
After that there was an attempt to run the check again.
Then after 3 minutes the battery turned off again and did not return the voltage even after 15 minutes
So the second patient was still successfully measured and what did we see?
These are not funny figures. No, it was certainly expected, but not at the level of 56-58% of the declared capacity. And notice! The first shutdown occurred with an accuracy of almost a second per second! Accuracy envy Skolkovo, the second battery is discharged just one second longer.
So we got the following results:
Shutdown voltage: 1,436V
The discharge current has always been: 0.592A
Discharge power 0,85W
Ampere given: 3528mAh
Power delivered to: 5,06W
With 6000mAh and 9W declared, it is not fat.
And here is the first re-measured after charging and by the end of writing a review
For comparison, 2x measurements were made rather notNew, but lively Turnigy LSD 2200mAh with a measured capacity at a discharge of 200mAh at 2180mAh. By the way, the test googling revealed a normal Alkaline D battery with a capacity of 17-18 amps!
And such results:
Shutdown voltage: 1,436V
The discharge current has always been: 0.592A
Discharge power 0,53W
Ampere given: 4166mAh
Power delivered to: 4,66W
Yohoho! What is it that turns out, buy fresh AA batteries of good capacity, 3AA to D adapters and they will make the comrades indicated in the review with a clean one at a lower budget price, longer survivability, greater capacity and a lower budget NiMh battery? Hmm ... Of course, I am somewhat disappointed, although onn-cell batteries have one distinct advantage, they hold 1.44V at discharge. Although I’m not sure about that either, because the iMax voltage twitched to 1.41V during the discharge of these batteries. Here are the things here.
I think to open a dispute and punish the seller for a 42% of the capacity of the batteries.
Well, I will think further than to replace the sausages in2x D batteries in the pump. Several lithium batteries are being suggested + any board similar to the MP2307 chip, one is bad, you will need to make a separate power button for this board, since the input voltage always heats the chip regardless of the consumer ... so I still will think ... Although ... maybe the pump and 4.2V will not cause problems with lithium? .. I don't know. But I know for sure that for a couple of alkaline D to give 1-2 times a month is not a hunt. Yes, and sometimes it doesn’t bother to think about ecology.
I hope that the review will be useful to you.
ps Dispute opened for a refund of 44% of the amount from 1500R. before bedtime. "The Dispute Reached An Agreement" immediately seller 665r. by the morning.
ws still decided to disassemble the battery and see what's there and how. Inside the battery is PE17500 1550mAh 18J23 3.7V 5.74wh
And apparently this is a plywood battery ZNTER (black and green)
I bought the EBD-A20H load and tested the capacity and various load modes.
So the load graph is 12 seconds from 0.5 amps to 2.1 amps in steps. Voltage did not fall below 1.42V
The same load for 12 seconds from 0.5 amps to 2.5 amps in steps, at 2.6A the voltage stopped. Voltage does not fall below 1.40V
Again, the test at 0.6A, the voltage dropped to 1.43V measured 3485mAh (discharge was without a load drop below 0.6A) / 5199mWh.
It is also found that above 0.7-0.8 amps at the start of the load test, it does not start for more than 2 seconds. Those. protection is triggered, and so they give 2.5A, you need to load started with 0.6 amperes.