Ryobi 40V battery - is it actually 36, drawing 40 "max?"

lumen aeternum

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Looking at a 3rd party battery for the big leaf blower since the Ryobi OEM are $150 for 6AH. This one is ~65. But the label says "36V (40Vmax)." So I wonder if its going to be straining the motor by providing under-voltage. Seems to me the blower is always at "max" - very hard to throttle the trigger on this one. The blower is a something402 - the put the label on the bottom where it scrapes on the ground!
 

Thetasigma

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Looking at a 3rd party battery for the big leaf blower since the Ryobi OEM are $150 for 6AH. This one is ~65. But the label says "36V (40Vmax)." So I wonder if its going to be straining the motor by providing under-voltage. Seems to me the blower is always at "max" - very hard to throttle the trigger on this one. The blower is a something402 - the put the label on the bottom where it scrapes on the ground!

Eh, I would steer clear of 3rd party batteries for these modern high power tools.

Regarding ratings, a 40V and 36V batteries are the same, just like 20V and 18V tool batteries are the same. They are just different ways of rating the pack for marketing bull excrement. 40V would be approximate full charge, 36V would be nominal/average charge of the pack over its discharge. Li-ion cells are usually rated as their nominal voltage, either 3.6V or 3.7V typically for a single cell. Put a string of 10 in series with monitoring and safety circuitry, and you get 36V.
 

BVH

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I've had very good results from buying three Dyson cordless vac 3rd party, larger capacity batteries online from diff sellers. They do, in-fact, contain the extra capacity and power the units as good as the OEMs.
 

lumen aeternum

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I think the Ryobi batteries refuse to recharge after not very many cycles, so I think I'll try the half price version; can't be much worse unless they outright fail.

Anyone know the 40V pinout? - I'd like to try the "plus to plus" trick to see if my "bad" battery really just needs to have the protection circuit "bumped."
 

idleprocess

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Looking at a 3rd party battery for the big leaf blower since the Ryobi OEM are $150 for 6AH. This one is ~65. But the label says "36V (40Vmax)." So I wonder if its going to be straining the motor by providing under-voltage. Seems to me the blower is always at "max" - very hard to throttle the trigger on this one. The blower is a something402 - the put the label on the bottom where it scrapes on the ground!

Ryobi "40V" batteries are standard li-ion cells (3.6V nominal) in a 10S2P configuration. Should come in at 42V (10x 4.2V) hot off the charger, 36V nominal (10x 3.6V), and as low as 30V (10x 3.0V) totally flattened - note that the specific voltages that the BMS permits may well be different. It's been some time since I measured voltages on the output terminals, but odds are there's some DRM involved (if not on the power terminal then via the T1 / T2 terminals) and the batteries may misbehave if you don't 'authorize' before discharging and the power equipment may well do the same; their 18V batteries certainly did this in some iterations.
 
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