BLF A6 Battery Check Question

LED Flashlights – General Info
1

Hi, I am a new BLF A6 owner with a question about the battery check mode. I have been reading the forum for quite a while learning about LED flashlights and proper use of batteries.

I finally decided to try the BLF A6 and have been very happy with it.
I understand that it is important to not over charge or let 18650 voltage get too low.

After a full charge my 18650 reads about 4.2V when I check it with my DMM. At that time when I do a battery check I get 4 blinks. I have read several times that a full charge will show 5 blinks.

I would like to know if other BLF A6 owners see 5 blinks at full charge or is mine a little off?

2

Yes, 5 blinks full charge on mine.

3

I’ve never seen 5 blinks on my mine, but I’ve never battery checked on a full battery. As long as you’re seeing 2 to 4 blinks you’re good.

4

Thank you for prompt reply. I am seeing 4 blinks at full charge 4.2V, 3 blinks @ 3.99V, 2 blinks @ about 3.84V. I recharge at 3.7 or 3.8.

5

from ToyKeeper's BLF-A6.txt file:

Hi singularity,

Would it be possible that the batteries were charged to more than 4.2v -- maybe you could double-check with a multi-meter? (what charger do you use for charging?)

Otherwise, maybe the flashlight's battery check is a calibrated a bit off (not sure if this happens or not).

Similar to others, I've only seen 4 blinks max on my Astrolux S1 and S41S.

6

Hi, d_t_a,

Thanks for posting, V. level/blinks chart very interesting.

7

Hello dta, I used a nitecore i4 to charge an LG HG2. Termination voltage is a bit over 4.2. Maybe around 4.21 or so by my multimeter.

8

i wouldnt; expect perfect accuracy from that

the only way to really do that is a ‘gas gauge’ which is a whole separate chip that phones have but flashlights never seem to

(it is a coulomb counter which may even have test resistors for calibration built in, usually with its own microprocessor)

wle

9

Hhhmm so would you say my charger is overcharging my batts severely? What would you suggest?

10

For what it’s worth, here’s how the voltage and flashes correlate in my RMM Moonlight Special driver with BLF A6 firmware:

  • 4.17 volts - 5 flashes
  • 4.12 volts - 5 flashes
  • 4.11 volts - 4 flashes
  • 3.91 volts - 3 flashes
  • 3.68 volts - 2 flashes
  • 3.39 volts - 1 flash
11

==no i would not say that, i just said not to trust the blink gauge
if you are concerned you can always use a calibrated meter
over 4.2 isn;t necessarily bad
it puts more juice in the battery
it may last 4 years instead of 4.1
no way to know really

i have seen 5 blinks on my a6 but i did not take the battery out to see what the volts are
i guess i just don;t think any charger is going to ‘severely overcharge’

wle

12

Thanks

13

I decided to revisit this and do some actual tests from a freshly charged battery.

So, after freshly charging a Samsung INR18650-30Q (4.20v), I placed it in the flashlights that use BLF A6 driver and do batt-check:

- on the Astrolux S1, batt-check does blink 5 times, so singularity35 is correct: immediately after a fresh charge, it could indeed read 5 blinks.

- on the Astrolux C8, batt-check also blinks 5 times

  • on the Astrolux S41S (quad-Nichia 219B) w/ 18650 tube, batt-check only blinks 4 times (maybe because it has a higher current drain, and had to go moonlight~~turbo~~>strobe before reaching batt-check mode, so maybe that drained the battery slightly enough to register 4 blinks?)

I haven’t tried to determine at what voltage the Astrolux S1 starts to blink 4 times though…

The Astrolux S2 batt-check (voltage count) is over-counting as always — 4.20v will blink out 4.4v (I remember ToyKeeper mentioning this bug for the BLF X5/X6v2 driver which didn’t seem to get fixed in the production drivers, over-counting by 0.2v usually, sometimes by 0.1v).

Also, I did another test, I’ve had a generic single-slot charger that came with generic XML-T6 flashlight, which I’ve not used since I read they tend to overcharge (I used them before, maybe a couple of times only on the junk batteries that came with that generic flashlight). But I decided to find out once and for all, how much do they really overcharge? (following the recent experience with a severely overcharged INR18650-30Q of 4.48v — I had thought before that the 18650 might explode when seriously overcharged — but the recent experience didn’t, so I guess I’ll just try)

So, I put some junk battery on the single-slot generic charger and charged the battery, when it turned green, I removed the battery immediately and checked the voltage to be 4.28v (so it really overcharges). I placed the battery in the Astrolux S2 to see if it would blink out any different. The Astrolux S2 blinks out 4.4v with this 4.28v 18650. BUT there is a difference: after it blinks out 4.4v, it subsequently blinks 3 times (actually 3 blinks with short pauses in between the 3 blinks, then a longer pause, then repeats). I think this might signify as a “battery error” condition (too high voltage) for the BLF X5/X6v2 driver?

14

How accurate is your DMM?

15

I’m trying to see if I can get it checked against a calibrated DMM, if I succeed I’ll report back. If it is not exact I don’t think it is very far off. For instance, brand new Energizer Alkalines test 1.5V. When my 18650 is charged in my Nitecore i2 Intellicharger final V. is 4.2.

16

Brand new alkalines should be closer to 1.62V, but I wouldn’t necessarily depend on it for DMM calibration purposes.

17

Just checked the battery check of my A6.

I put a rather full Panasonic GA in and let it run in turbo.
After letting it run for about 20s I switched to battery check and got 4 blinks. Now I waited for the voltage to recover and after some time it blinked 5 times.

Right after seeing the blink I pulled the battery as quickly as possible and measured 4.144 V ±0.3% with my DMM.

Edit: Repeated the process a few times and the lowest voltage I could measure was 4.14 V ±0.3%.

18

What battery do you put in the A6? Protected or not? Button or flat top?

19

I am using unprotected ones with flat top or flat top with solder blob.

20

I am using Samsung 18650, 30 Q, unprotected, flat top. I have been very happy, with battery and I have been really satisfied with my BLF A6.