Ryobi 18v li-ion; aftermarket batteries or new cells?

[KevDIY]

All my Ryobi li-ion 'one+' batteries are starting to run down quickly now, so I guess they're nearing the end. Aside from the low capacity/slim ones, Ryobies replacement seems to be a 4Ah version these days, which would be great. But they're really quite expensive, around £70 each (and I may need a new charger too if my older model can't charge them).

There are a few varieties of new after-market/3rd-party/compatible ones on ebay, at about £40 each and (a claimed) 3Ah, which seem good value if they're any good. Has anyone got any experiences of these over time - do they seem decent or are they not as good or long lasting as Ryobi originals?

Or, I could replace the cells in my current batteries; it would cost slightly less and I'd know what quality of cells were inside, but there'd be more risk of something being incompatible. Has anyone found good quality cells (i.e. designed for high current) that work well with the original 2.4Ah li-ion battery cases/electronics?

Many Thanks,
Kev

 

[pinenot]

The charger (assuming nothings wrong with it) should charge the re-celled battery pack ok, as the voltage drop off when charging is nearly done is triggered by the filling cells themselves. Also the batteries packs are protected with a temperature cut off sensor, so it must be refitted exactly as the the old cells are.
But back to the current battery pack, how many charge cycles are we talking about approx? and when you say run down quickly now, can you expand on that i.e. does the charge stop sooner than it used to, any anomalies etc. etc. ...pinenot

 

[KevDIY]

Ah, interesting, thanks. Possibly I could get larger capacity cells too, then. I've surfed around the net a bit and seen people replacing the cells, so I'm sure I could manage it well enough. But there do seem to be a number of pit-falls to avoid like the cheap cells with high internal resistance have low current handling, or protected cells don't work properly and that kind of thing.

I can't say I've measured anything very scientifically, but the time it takes to run down the fully charged batteries is getting quite noticeably less than it was, though they don't seem to be performing badly/weakly otherwise, so any tail-off in performance would have to have been gradual enough not to notice (I don't have any new ones to compare). I haven't really timed the charging, so I don't know if that has changed or not, but the indicator lights still work as normal - they aren't showing any errors yet.

To be even less helpful, I can't remember exactly when I bought them but its closer to several years than a few; it may not be, but if the four digit number on them is a date then I suppose 0208 may mean that they were made in feb 2008? During that time they've been in frequent DIY use as I do quite a lot of stuff for friends and families many weekends/evenings so they probably got charged several times a week on average, but they haven't been used all-day everyday like in trade.

Cheers
Kev

 

[pinenot]

Beware going for higher capacity cells, the charger was designed for a calibrated input of both v and amperage and at some 6 years of age may not rise to the occasion. Assuming you can get back to what they were like in the beginning, I think that's a better option.
What you say about choice of replacement cells is correct, some will be cheap but could prove disastrous, that's not to say costlier ones will fair any better. Knowing your cell supplier is more than half the battle I'm afraid...pinenot

 

[ibruceuk]

I'd stay away from the cheap ones on eBay personally. I tried some and while they seemed ok and worked fine on the drill, when I tried them on the impact driver or recip saw they cut off as they couldn't supply the higher current that these placed on the battery.

Got a full refund from the seller but was a lot of hassle.

Does anyone know of any good suppliers of LiIon cells?

 

[big-all]

yes you will need a lion charger for the 4ah
is the potential saving worth the effort??
3ah recell £10.33p per ah
4ah ryobi £10.75 per ah

 

[ibruceuk]

.....
4ah ryobi £10.75 per ah

I'd love to know where to get a Ryobi 4.0Ah for £43!

 

[KevDIY]

I'd stay away from the cheap ones on eBay personally. I tried some and while they seemed ok and worked fine on the drill, when I tried them on the impact driver or recip saw they cut off as they couldn't supply the higher current that these placed on the battery.

Got a full refund from the seller but was a lot of hassle.

Does anyone know of any good suppliers of LiIon cells?

Ah, thanks. I believe the life of Li-ions is very sensitive to temperature; if they have a high internal resistance then they'll get warmer and also not deliver as much 'umph'. I guess cheaper cells may be how they undercut Ryobi; if thats so then its probably a false economy for things that try to drain them fast, like circular saws, though probably okay for torches.

Hmm, so its going to be either replacement cells or original batteries then. There are some cells on ebay that have their internal resistance and current drain specified, 20A, 30A that kind of range.. if you can trust that they're genuine anyway. But they aren't the cheap ones - it'd cost me about £65 to replace the cells in a couple of 2.4Ah batteries, which is about the same cost and not really much more total Ah than a shiny new Ryobi 4Ah one.

Perhaps re-celling is not massively worth doing either then, unless theres a cheaper supply of decent cells somewhere anyone? Although.. it could still be worth putting some cheaper cells in the old batteries 'just' to be used for less demanding tools, would spare the good batteries for where they're needed.

Cheers
Kev

 

[KevDIY]

yes you will need a lion charger for the 4ah
is the potential saving worth the effort??
3ah recell £10.33p per ah
4ah ryobi £10.75 per ah

Yeah, I do have a li-ion charger, but its an older ryobi type not the latest 'super charger'. Their website says the 4Ah battery is not compatible with the standard one+ charger; I wasn't sure if by that they mean mine or the old ni-cad version, and unfortunately Ryobi have not responded to either message I sent asking.

Hmm, yes, its only marginally cheaper to re-cell at the prices I've so far found, so not IMO worth the effort and risk of it not working out well, unless we can find some good, cheap cells.

But even then I haven't found the Ryobi 4Ah Li-ions for less than £65 (except from private sellers who I have no way of gauging the trustworthiness of). If you know of somewhere that does them for £40-odd that would be most interesting! Its even equivalent on price to the 3rd party 3Ah ones.

Cheers
Kev

 

[KevDIY]

If its of interest to anyone I've opened one of my Ryobi 2.4Ah batteries to see what cells are in it. There are 10 red coloured cells by Sanyo, number UR18650SA. I can't immediately find any for sale (other than in huge quantity), but searching for their specs one data sheet suggests:

They're rated at 1.2Ah to 1.3Ah, 3.7v nominal. Max discharge current 20A. Recommended to be charged at 0.84A for three hours, or max quick charge at 1.2A; charge at 4.2v (constant voltage with limited current). Discharge Cut-off Voltage = 2.75V. (all at 25 degrees C where applicable). It doesn't mention that they're protected, though it doesn't say not; I heard somewhere that replacements shouldn't be but I can't say for sure. Of course, thats per cell, they must be doubled up in the battery to only reach 18v with 10 cells, so thats why the battery is 2.4Ah, the max battery current would 'presumably' be more like 40A and the max charging currents also doubled, or maybe a bit less if there are problems matching the cells.

There is also some stuff about storage life/temperatures which makes me remember I could have treated mine better - 1 year -20~25celsuis, 3 months -20~45celsuis, 1 month -20~60celsuis. And its interesting about the charge time; maybe they would last longer if Ryobi had given me a standard charge option on the charger, for when time wasn't of the essence.

So I guess I'll have a look and see whats available; my initial feeling is that due to there being 10 high-ish current cells it could be quite hard to find anything at a competitive price.

Cheers
Kev

 

[catlad]

I have bought a few batteries of this company and have satisfied. global batteries

 

[KevDIY]

Well, so far I can't find any reputable brands that match/exceed that sort of spec at much under £50 set. And even then there are all sorts of questions wrt what age/condition the cells are in and never quite knowing how it will work in practice. As the genuine, fully compatible and much bigger capacity Ryobi batteries are only £15-£20 more (unless big-all knows of a cheaper source?), its probably not worth the effort or risk IMO.

I was just hoping there may be a cheaper way; I also have the dewalt 18v system and their batteries are if anything similar or a teeny bit cheaper and perhaps a bit more sophisticated. But then they did change the fitting recently to do that, whereas Ryobi have kept theirs compatible with most existing tools; if that alone stopped the batteries being a few quid cheaper it would be worth it IMO. And based on my old 2.4Ah batteries the new 4Ah ones should earn their keep.

Cheers
kev

 

[KevDIY]

I have bought a few batteries of this company and have satisfied. global batteries

Ah, you posted whilst I was typing the last post; thanks very much, I'll check them out!

cheers
Kev

 

[Aragorn84]

18650's are very common lion cells...

http://www.amazon.co.uk/3100mAh-Protected-Panasonic-Rechargeable-Battery/dp/B009UYHJC4

http://www.amazon.co.uk/gp/product/...m=A3P5ROKL5A1OLE&pf_rd_r=018YCKNAYWDXDESK0S3Q

buying 10 wont be cheap though!

 

[KevDIY]

Yes there are loads, many with very high capacities. But cells of that type are not all the same; they vary a lot in performance. Sadly none of the cheap ones I can find are suitable for this type of high current application, so you're right its a costly thing. IMO pretty marginal vs buying a whole new battery, and far less certain.

EDIT I think I'll buy new ryobi batteries, then when my old ones finally give out completely I'll revive them with new cheapo cells but not to use in serious power tools, just the torch and maybe radio etc.

Cheers
Kev