The problem with replacing a NiCad battery with a NiMh battery is the charge circuit would be designed to provide a trickle charge of 1/10C. If you charge a NiMH battery at that rate for prolonged periods after it is fully charged, you will damage it (https://en.wikipedia.org/wiki/Nickel%E2%80%93metal_hydride_battery).
In this case, the charge circuit is an 18 ohm resistor tied to 5V. Assuming a fully charged cell floats to 1.4V, the battery pack will end up at 4.2V which will yield a charge current of ~44mA. So, at a minimum, if the battery capacity is 440mAh or less, consider replacing it.
I would not recommend leaving you unit on for prolonged periods (10- 20 hours)
I ended up replacing mine with a NiCad battery from a phone I no longer use.
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On Mon, 12/18/17, Ewan Colsell ewanuno@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:
Subject: Re: [Simmons Drums] Re: SDS9 backup battery and schematic.
To: Simmons_Drums@yahoogroups.com
Date: Monday, December 18, 2017, 6:14 PM
i replaced the battery in my
sds9 with a 3.6v nimh battery. the original was a nicad, but
the nimh is fine.
the battery i used was a
replacement for a wireless phone if i remember correctly.
ewan.
On 16 December 2017 at
07:04, Realm Steel realmsteel@...
[Simmons_Drums] <Simmons_Drums@yahoogroups.com>
wrote:
I replaced my battery about 5
years ago.Do a google search for "NI-MH 3.6
V/80mAh".I may have bought from
Newark.
Thank
you,
Realm
Steel
#yiv4980294552 #yiv4980294552 --Message
Re: [Simmons Drums] Re: SDS9 backup battery and schematic.
2017-12-19 by S Gallo