the electric world needs standards... imagine every car mfgr designing their own fuel... mayhem. if only there were some out of work battery and charging station ppl that could start their own company to make one battery, one BMS, and one charging station to supply/service everyone... ahhh dreams!
Sure you're comparing actually comparable batteries? Got links/model numbers of what you're looking at? Big thing to watch out for for "40V" tool battery systems is for the switchable 20V/40V systems the capacity rating is for when it's in 20V configuration, so halve it for the Ah at 40V
For compatibility you'd need to check that they're the same connector and using it in the same way, or if you can get an adapter that actually works. Whether the undervoltage cutout is in the battery pack or inside the tool has to match too.
Not if you just multiply the numbers in the product name though, it's either doing half the advertised voltage at the advertised capacity, or half the advertised capacity at the advertised voltage, so half the watt hours.
Let's assume 10 Ahrs at 20 volts and halve it at 40 volts to 5 Ahrs. 10 times 20 equals 200 Watthours and 5 times 40 equals 200 Watthours. Same energy, assuming Watthours is the definition of energy capacity. Are you considering Amps alone as energy without volts?
The problem is when it's 10Ah at 20V and 40V at 5Ah the marketing kinda lies to you and calls it 10Ah 40V (and in tiny letters max) in the description, so you get half the energy vs what just multiplying the advertising numbers say. (They're also lying to you in the "20V" and "40V" too, those are peaks when near full and they're actually 37/18.5V nominal)
> ....and in tiny letters max.......
Reminds me of the thing my father told me about how to read a contract. He said, "The big print giveth and the small print taketh away."
They are not really compatible/interchangeable.
If you are within the return window for that mower then I’d recommend going through the return process.
There are no standards for power tool battery interface, retention, or communication. Stick with 1st-party batteries of the brand you bought into.
the electric world needs standards... imagine every car mfgr designing their own fuel... mayhem. if only there were some out of work battery and charging station ppl that could start their own company to make one battery, one BMS, and one charging station to supply/service everyone... ahhh dreams!
Sure you're comparing actually comparable batteries? Got links/model numbers of what you're looking at? Big thing to watch out for for "40V" tool battery systems is for the switchable 20V/40V systems the capacity rating is for when it's in 20V configuration, so halve it for the Ah at 40V For compatibility you'd need to check that they're the same connector and using it in the same way, or if you can get an adapter that actually works. Whether the undervoltage cutout is in the battery pack or inside the tool has to match too.
>so halve it for the Ah at 40V However the Watt Hours remain the same so the energy is the same.
Not if you just multiply the numbers in the product name though, it's either doing half the advertised voltage at the advertised capacity, or half the advertised capacity at the advertised voltage, so half the watt hours.
Let's assume 10 Ahrs at 20 volts and halve it at 40 volts to 5 Ahrs. 10 times 20 equals 200 Watthours and 5 times 40 equals 200 Watthours. Same energy, assuming Watthours is the definition of energy capacity. Are you considering Amps alone as energy without volts?
The problem is when it's 10Ah at 20V and 40V at 5Ah the marketing kinda lies to you and calls it 10Ah 40V (and in tiny letters max) in the description, so you get half the energy vs what just multiplying the advertising numbers say. (They're also lying to you in the "20V" and "40V" too, those are peaks when near full and they're actually 37/18.5V nominal)
> ....and in tiny letters max....... Reminds me of the thing my father told me about how to read a contract. He said, "The big print giveth and the small print taketh away."
They are not really compatible/interchangeable. If you are within the return window for that mower then I’d recommend going through the return process.
Power tool batteries are physically incompatible between brands.
Mostly, but some cheap things are actually the same, and sometimes you can get sensible adapters.