Youshiko YC4000 (official uk 2026 version) intelligent aa aaa professional standard battery charger with 1000mA charge current + usb port

Really happy with this. The functions are good though refresh often seems to go on for many days. I love the chance to choose charging/discharging current, the granular control of each battery, and the general ease of use. 20 months after buying it, it's still working like new and it's been used regularly. Only one improvement I can think of I'd like to see: occasionally a battery will discharge so deeply that it won't charge it at all in this charger. I send the battery to a friend who has a charger that allows him to brute force charge it and then it's often fine. I wish I could do that with this charger.

Just great. This is an almost identical but improved version of the well regarded Technoline BL/BC-700 (or Lacrosse BC900) - improved by the addition of an extra 1000ma charge setting for very fast charging and a 5V/1A usb output for phone/tablet charging. Note that it is not recommended to do fast charging often as it apparently reduces the life of the battery, the charger defaults to the minimum 200ma charge rate,which is very safe, you can also select 500ma and 700ma (the corresponding discharge rates are always half of the charge rate. This is one of the best chargers you can buy, see these two youtube reviews (of the virtually identical BC700) to see why it might be a better choice than an even more sophisticated model. https://www.youtube.com/watch?v=C3SBjrhANSs https://www.youtube.com/watch?v=JslHWoXpnEw Be warned that it is not a simple device, and the instruction manual is very concise, but once you get used to the controls it is brilliant. You can select individual batteries at any time and change the charge/discharge current or mode (charge, discharge, refresh or test) - to do this you press 1,2,3 or 4 to select a battery and then you MUST press the mode button, even if you are just changing the current (in which case you have to cycle through the modes to get back to the original mode - a little design fault there). Alternatively you can remove the individual battery and reinsert - then you have 8 seconds to select the new current/mode. It displays, for each battery individually, charge/discharge rate (in mA), the battery voltage (which should be 1.4v - 1.5v for a fully charged battery), amount of power (in mAh) charged or discharged in the current cycle (this resets to 0 mAh if you change mode or current) - and the time each battery has been charging/discharging in the current cycle (which resets to 0:00 (h:mm) if you change the mode or current). You can even change the display setting individually for each battery. Test mode is genius, it first fully charges the battery, then completely discharges to measure the capacity, and finally fully recharges again! The final display shows the voltage of each battery, the measured capacity during the discharge AND the time taken for the full discharge (this was confusing at first as I thought it would show the time taken for the last charge cycle) - which is great info - you can put the batteries in at night time, set to test mode with 500mA current, and the next day you have fully charged batteries and precise info on their capacity. Note that the capacity will display "---" until the full discharge cycle completes, and if the capacity is greater than 1999mAh the display switches to Ah units (eg 2.50Ah = 2500mAh). Refresh mode repeats this discharge/recharge cycle until no improvement is detected in the discharge capacity (up to a maximum of 20 cycles) - beware that this can take several days for large capacity batteries on a low current charge. Some small cons 1. It failed to detect that one battery was fully charged and started to overheat - it stops charging once temperature gets to 55ºC - but it's a little bit annoying to see a battery stuck at 1.46v for over an hour (it should switch to trickle charge once full). This may be a dud battery, it's an old high capacity 2700mAh one that now only holds half that charge. 2. Batteries are almost (but not quite) touching, so some heat does pass to neighbouring batteries. 3. There is no simple discharge cycle - the mode named discharge - does discharge the battery but then fully charges it (to remove memory effect in NiCD batteries) - you have to keep an eye on the LCD display and remove the battery if you want to store it discharged (even the test mode, which fully charges and discharges to test the capacity, does a final full charge cycle) 4. No backlight on the lcd screen so cannot adjust settings in a dark room (UPDATE: you can plug a usb light in the usb port!) 5. No cover or case to keep dust out of the charger. But, these are minor issues - the individual voltage and current measurements and settings are great for a device at this price. At first I was a bit worried because it looked a bit cheap and was confusing to use - but after playing with it for a few days and charging a few sets of batteries I'm really happy - my simple uniross fast charger was really not fully charging my batteries - now I have full control NB as an above reviewer wrote, insert the batteries properly - push back on the negative contact and then push down the postive end of the battery to fit it firmly in the slot. edit: One more plus point - uses a standard 12v power connector, so can be operated from solar power easily (if that's an option) edit: you can use the superior manual for the Lacrosse bc700, which is a bit easier to read, also tells you that when the capacity exceeds 1999mAh the display changes to Ah, so that 2500mAh will read as 2.50 Ah on the display. http://www.lacrossetechnology.com/bc700/manual.pdf [UPDATE 8/4/2015: The charger is working well and I am very happy but just want to mention that on the lowest current setting of 200mA it sometimes fails to detect a delta-V drop in voltage at full charge and stop charging. I have only noticed this with uniross hybrios and only at 200mA, it may be a characteristic of that particular battery model. It happens less than 10% of the time and I mostly use the 500ma current in any case, so it's not a big issue for me. EDIT 23/4/2015: Apparently I just to need to be patient and wait a lttle longer, about one and a half times the rated charge may need to be supplied sometimes - it DOES eventually reach full charge - my mistake]

I purchased this unit as a replacement for my failed BL700. That one never worked properly with regard to the buttons but thankfully this charger by Youshiko has worked flawlessly so far. It has all the functions of the BL700 and although it has slight differences regarding the styling and feel of the buttons it works just as well. You can discharge, test and exercise the batteries as well as charge them of course and all independently in their own channels. You can charge AA in one channel and a AAA in the next of course. You can discharge another whilst also charging the next. All combinations are supported. I have already gone through my entire stock of 20+ batteries and given this unit a thorough test and I am happy to report no weird issues or bugs. All batteries were charged up without a fuss. You can really ramp up the charging current but this can heat up the batteries somewhat. I used a cooling fan to aid bringing the temps down when charging at the full 1000 mA rate. I did read a review where someone had tested this unit for high over temp cut off and it didn't work but I have not replicated this due to not wanting to cook my batteries. They did get very hot so I would not want to leave this unattended for any length of time without checking how hot each cell gets. Other than that, I have noticed a small mark on the LCD which is a shame. The mark is under the plastic display on the actual LCD panel so would have been damaged during manufacture. It loses a star for this. Thankfully everything else works ok and overall I do like the unit for charging and conditioning my batteries.

I have bought many chargers in past like Maha, Technoline, AccuPower, Energizer etc as I charge batteries every other day, I rely on them heavily for my work. But I must say, this New UK Model Youshiko YC4000 to be overall better intelligent battery charger and value of money, probably best intelligent battery charger I ever bought. I have learnt from my own experience with one of my old charger ( Don’t like to name the brand ), lose connections may not charge at all or charge slow or some time make you charge again, total waste of time. But in Youshiko YC4000, inserting the batteries in charger, Gently need to tuck in the negative end under a lip in first and then push the positive end down and when taking the batteries out , Gently you need to push back from the positive end towards negative end and then pull out the batteries. Which I think it’s a clever and neat design, as batteries connections in each slot with charger are very secure. As it should, secure connection to achieve accurate charging. Youshiko YC4000 refresh function is 100% better than other chargers; I have charged nearly 3 years old batteries which my other chargers refused to charge. I have already saved money and I am sure, I will save more in coming days and weeks, as I have more old batteries. I have used this charger for around or over 30 hours constantly with no problems at all. I have used Charge /Discharge / Refresh function, I have not used the test function yet. I have charged my phone with the USB Port, All functions works very well. It does exactly, what it says in the description of the product. Power Supply is a UK Plug but it is 110v to 240v, so this can be use worldwide with a simple travel adapter. Also there is option to buy car adapter but not included. This YC4000 is very similar to Technoline BC700 ( with max 700mA ) but this Youshiko YC4000 have more powerful charge with 1000mA and offers more options, like USB output and car adapter option on much cheaper price than other brand chargers. It is Professional standard, high quality, you will get more for your money, highly recommended. I emailed Youshiko (email address found in instruction book) and asked for a PDF file of the instruction book so I can have it in large print and I received it, with in 2 hours, Instruction book found to be quiet good. Very good customer services. I must say again, probably one of the best intelligent battery charger, I ever bought .

Bought this to replace a (significantly more expensive) old charger, which seemed to be over-charging cells. The YC4000 has been great in really letting me understand the state of the various cells I had lying around. Have tested this over the past couple of weeks and I'm reporting my findings here. First off were a bunch of old NiCd AA and AAA's. Through years of abuse and neglect, these had discharged completely for a long period of time. This charger indicated they were duds. Even if I could have refreshed them to half of their original capacity using the widely-published "paperclip trick", who wants a 500mAh AA these days? Binned them. Next were some Uniross Hybrio AAs (Eneloop equivalents). Originally, all eight of them were reported by this charger as having a capacity of 1400-1500mAh. Put them all on a full refresh cycle over the next few days and I've now got a great set, with capacities from 1950mAh to 2050mAh (rated at 2100mAh). Other fast chargers would have just continued to toast them before they became completely worthless. Final test was for a pair of AAA NiMH. The refresh cycle completed successfully, although it did claim a final capacity of 650mAh for a product labelled as 550mAh. Will try again in the future and see what happens after a few more discharge-charge cycles. Operation? Well the user manual looks a little complicated, having multiple modes and display settings, but really it isn't. Just shove the cells into the charger and provided you've got them the right way around then this compact unit will happily recharge them, albeit a little slowly. Want to charge a little faster? Provided you do it within 8 seconds (which is easier than it sounds), then just press the Current button. Easy. Exploring more of the functions, I've had a play with all of the modes. "Charge" is a bog-standard traditional charger approach - top up whatever capacity the cell has right now until it is full. "Discharge" is a bit slower, but kinder to the cells by completely discharging and then charging from empty, thus avoiding the "memory effect". "Test" is slower again, having to fully charge the cell before doing exactly the same as the "Discharge" cycle. This one is to see exactly how much capacity you really have available to you. "Refresh" is even slower still, but does the best job it can of restoring your cells back to full operation (see above) by continually cycling through a discharge-charge loop until the measured capacity does not increase further. As I found out in my first test, if you select a charge current of 200mA and have 2100mAh cells, then this can take days to complete. Other things: while the display looks a little primitive, it actually tells you everything you need to know. Getting the cells out after charging can be a little fiddly (especially from the middle slots with cells either side) but isn't worth losing sleep over. I don't know exactly how heavy I was expecting the unit to be, but it's very light - possibly feeling a little too light and flimsy on first inspection, but it doesn't seem to flex at all, so I guess it's well-built, but just not very heavy. In summary - a great product that does the job nicely. If you have 8-10 old rechargeables lying around, the extra cost of buying one of these over a cheap charger will probably pay for itself by refreshing the cells you already have back into life. Recommended.

This has saved me it's cost in the first round of charging my batteries by rejuvenating cells I was going to throw away as I thought they were dead. + A charger that can charge a single battery + Will 'refresh' charge batteries which can be a long process (some took six days) but well worth it as some 7dayshop ones I had and not used for three years were brought back to life by this charger, when my two other simple fast chargers had indicated they were for the scrap heap. It took so long because they were 2900 mAh batteries and I purchased for my cannon speedlight 3 years ago and only dusted it off (along with the batteries) this month. They would charge in my energiser charger for 15 minutes and indicate fully charged and subsequently only work for an hour in a portable radio, so clearly not right, my other Jessops charger would not even charge them. It is a great feature as it repeatedly charges at 200 mA and discharges at 100mA until the battery is as restored as possible back to original capacity. + great display which shows you exactly whats going on and indicated the status of the battery. Each cell has it's own display and is treated individually. - Shame it isn't USB lead to power the charger as that would reduce the volume of stuff I have to carry when I go away as always have a multiple UBS plug adaptor with me. + But it has a USB output for charging phones/tablets etc. so suppose I could use that. +/- Makes me feel a bit of a geek looking at the units of measurements to see how the batteries are doing and how they are improving their capacity. Something quite exciting about bringing a dead battery back to life! and saved me a fortune in buying new batteries so I can rely on them in my flash/ other gadgets. - Wife thinks I'm sad now. + The company emails a copy of the instruction as a PDF which is great, as I always end up binning the packaging only to regret it later. I PURCHASED THIS AT THE NORMAL PRICE AND USED MY OWN MONEY SO IT'S AN UNBIASED REVIEW. Would buy again.

While the various modes operate very slowly, I guess that is necessary in order to protect the battery chemistry during charging, testing or recovery. The device is compact but of solid and well made construction and the screen is clear. Thus far I have been very impressed with the YC4000 and fully expect it to live up to its promise. And importantly, Youshiko were very prompt when replying to my request for an A4 copy of the User Manual - well done.

What I know about battery tech you could write on the back of a postage stamp, but with so many battery powered gadgets in use around the house these days I keep a box of rechargeable 'amazon basics' AA batteries by the door. Those betteries get used, depleted, recharged and placed in the box again ready for next use. (It never ceases to amaze me how fast video game controllers with gaming headsets can deplete AA batteries). Anyway, recently I'm getting a lot of family waving batteries from the box at me saying 'but its not working'. Maybe some of the batteries are failing or faulty. More likely some disorganized people are putting their discharged batteries straight back in the box - rather then recharging them - when they go to get replacements ..... then the next person along is pulling out the depleted ones. Anyway, We're cycling batteries at such a rate I wanted to be sure that the batteries are still 'good' and - when people can be bothered to recharge them - they were being properly recharged. I had been using an old energiser AA charger, the reliability of which I was also starting to question, so I read some reviews and this YC4000 seemed very well thought of by those who understand such things. Here's my opinion. The unit comes in two parts, the charger itself and its power pack. The power pack goes into the wall socket and has a short lead which plugs into the charging unit. The charging unit itself is small, holding up to 4 AA batteries closely packed side by side with a small display and three buttons under the batteries. The build quality of the charger is not reassuring. When I put it on the table it wobbled. The body must be warped in such a way that the four small plastic feet under the charger, one at each corner, are not level so it will not stand 'flat' on a level surface. To me that shouts "poor build quality" - as well as causing a very annoying wobble every time batteries are inserted or buttons are pushed. Not good in a £32 charger. Beyond the wobbly feet, the display is a bit distorted on the lower right (that oily sheen you sometimes get on these gray displays), but still readable. The buttons are also a bit 'clicky/sticky', maybe that will ease off in use. I'm hoping that 'what we're paying for' is the clever charging electronics because its clearly not the build quality of the device. Put in batteries and they charge at the minimal 'default' 200ma rate, so the basic use is quite simple. The charger has several cleverer settings - individual battery charge/refresh/test/discharge and a range 200 to1000ma charge current settings. Understanding and setting these settings is another matter. The manual is small ,in small type and has the writing style of those deliberately convoluted English comprehension tests - never use a flowchart if a dense paragraph is available. And its more than just 'press this then press that', its a time limited 'press this then press that within X seconds' sequence Not overwhelmed with first impressions, but I'm hoping this charger lives up to the hype.

Pour charger des batteries au Royaume Uni, ce doit être parfait car l'unique chargeur est à la norme britannique. Mais pour la France et la Belgique c'est impossible car il n'y a pas d'adaptateur de prise prévu.