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heavy on powerchair batteries. Partly because I am very heavy!
Partly because I use full size hi
powerchairs that place huge demands on batteries anyway, partly because
I don't sit at home all day. I actually
use and abuse my powerchairs a lot. It's batteries last between 6 weeks (read later!) and
15 months at very best.
All the batteries on this page are the same "size" Group 24" (or
all fit the same powerchair and scooter
battery compartments as well as my van and almost all large hi end full range outdoor powerchairs.
There are some very unusual battery choices on this page tested purely out of curiosity!
So you don't have to. If you want the quick answer and have a moderately
powerful and "normally" programmed powerchair buy an MK. If you want fast charge
capability, more power (torque) in a faster or reprogrammed powerchair that
draws a lot of power then you want the Odyssey AGM batteries. Non of the rest
are really worth even considering.
batteries and charging systems very well
having sold batteries over many
years and have tested a good few deep cycle batteries to destruction personally
over the last 12 years. Many more of them than you would expect. And have fitted
totally unsuitable ones on purpose too just to see what happens as you do!
And its not pretty. I do this both for
my own knowledge and so that you sane people don't have to! I log everything too, (end of
day voltage/state of charge, temp, hours use etc) so know what works and why.
With THIS. If you want to KNOW about batteries
and are a control freak then get one ASAP!
ABXAGM 70ah Deep
Cycle and Starter battery.
ever fitting ANY new batteries you really must charge them individually
with a decent multi stage charger with the correct finishing voltage for the
type of battery.. In the
case of these two below, it was especially important as my trusty voltmeter told
me that one was 12.3 volts straight out of the box! That's l very low.
The other was
at 12.6 volts which is pretty normal and almost fully charged. That was expected. Had I just fitted them, as most normal people would
do, then they would be very
unbalanced. 12.3 volts equates to a half discharged battery or less. The other one was
nearly fully charged. Continued below...
ABXAGM medium |
Had I then
either used the powerchair with them as they were or plugged the
powerchairs charger straight in after fitting, then the batteries would be
damaged in both cases. I really wonder how many people do this? If I drove the
powerchair the "flatter" battery would get "discharged" far too low while the
other was only partly discharged. Deep discharge hurts all lead based batteries.
If I had charged it in a "series connection" or string (as it is when fitted in the powerchair or
scooter) then I would have overcharged the almost fully charged battery causing
damage and gassing of the electrolyte and probably still not have fully charged
the half discharged one. Because the charger only sees the TOTAL voltage of both
batteries. It has no way to know one is very low.
In this case here (picture above) I am using my Ctek
8 stage charger (7 amp) to charge two new ABXAGM Deep
Cycle and Starter (dual purpose) batteries. I chose the 14.7 volt
setting because generally this is correct for all AGM
type batteries. 14.4v is OK but 14.7v is usually recommended for AGM type batteries.
14.2V to 14.4 volts is correct for most GEL type batteries that are used in most
powerchairs and scooters. So a 14.4v charger (per battery) or a 28.8v charger
like the one your scooter or powerchair comes with will safely charge either
type of battery. If not totally matched. It will work fine with both AGM or GEL. If you use AGM
batteries however it helps keep all their cells in balance by using a single AGM
14.7V battery charger every month individually on each battery although its not
Get this wrong though and overcharge a GEL battery
above its recommended voltage using a AGM charger and
typically HALF its life expectancy! First I charged each one
individually. so both were "fully charged" to begin with. Then I connected them together (in parallel with positive to
positive and negative to negative) and left the charger on a maintenance and
float charge for a couple of days to make absolutely sure they were both at the
same exact 13.3v level of charge on "float" while I was ready to fit them.
batteries were cheap! I am testing them to see if they are any
good in a powerchair for my purposes. Obviously I (we all) need the Ah (Amp Hours
rating) to be
as high as possible for best range and because it lowers the average daily
discharge level as a percentage and so extends battery longevity.
Put simply the greater the Ah rating the longer they last in theory! They are Absorbed Glass Mat type
batteries (AGM) not Gel (or Gelled Electrolyte) batteries. Good quality
Gel batteries (like MK have typically 500 cycles at 80 percent depth of discharge
capability under lab conditions.
These AGM batteries like most AGM batteries typically do a few less cycles (400)
but are better at making the big currents that my own powerchairs demand. Much
better. And they charge faster too.
supposed to have 400 Cycles at 80 percent Depth Of Discharge.
(D.O.D.) And have extremely high CCA (Cold Cranking Amps) so that means they can
deliver a lot of current fast! They can start a truck! That's what I like
to see. Going by the figures alone without testing
these they should perform much like the
Odyssey that I
normally use then, only cheaper and with bigger Ah rating...
We will see! I have
high hopes for these batteries. These arrived three days ago so I will
update the results for these as soon as I have any comments. I expect they
will not last as long as I would like at this budget price. We will see! 02-March-09
09 - March 09
Update... After a few days use I sent them back for a refund. They were
short of range and of "power" or "amps" with heavy voltage drop under
load. They should have been OK so I suspect one
of them was faulty. Never got a chance to load test them individually to find
out as the carrier came to collect them too fast! And they are being replaced
with a set of MK Gel batteries this week free of charge. Remember that one was very
discharged when it arrived? That one was probably faulty.
Obviously these are (were) the same size as
most of the batteries on this page at roughly 260mm x 210mm high x 175mm wide.
They fit MANY large powerchairs and scooters. They are sealed and cant spill.
The acid is stored in a Glass Mat which also forms the plate separator in the
battery. They are recombinant (Turns Oxygen and Hydrogen gasses back to water)
like most wheelchair batteries are so provided the correct charging equipment is
used (never over 14.7v) then no electrolyte is lost and they cannot be and don't need topping up!
Shame I cant tell you more about these. Will test another set soon.
(Smaller Group 34) and the
GEL Group 24 batteries here are
fitted by most of the major mobility manufacturers.
This is all most people REALLY
need to know. They are the batteries that 90 percent of all scooter and powerchair
users should really buy. Both use exactly the same technology. Both are equally
These are, for most people, the Rolls Royce of Deep Cycle
batteries. They both give the maximum number of deep discharge cycles that
you will get from any mobility battery.
but the best sensible QUALITY solution for the job. Both
are extremely similar. Both are GEL batteries (Rather than AGM) and sealed and
will not gas or spill under normal use. Safe for flying, non spillable.
Both of these high
quality batteries will give 1000 cycles at 50 percent
discharge, Which is better than the Optima, the Hawker Odyssey and the ABXAGM
AGM batteries (top of page) and both give
500 cycles at 80 percent depth of discharge which is again about
better than AGM type batteries on this page. For the average user on an average
Wheelchair or Scooter these
really are what
you need. Don't be tempted to buy anything cheaper. That's for mad people like
me to try as an interesting experiment. BECAUSE IT DOESN'T USUALLY WORK OUT
CHEAPER IN THE END!
batteries like these normally offer better cycle life,
AGM batteries offer
faster current (Amps) release if all else remains equal.
Only you can know which is
better for you through trial and error or previous experience in your specific
application. For 99 percent of powerchairs and users these are the best
However I still manage to kill both of these
batteries in 10 to 13 months on average. That's not
considering that I really work batteries hard. You only get around 500 cycles with
you discharge them by around 80 percent daily and charge them with a correctly matched
charger every night. Most people do not discharge them so
heavily though so get longer life.
If you discharge them deeper, take bigger
currents out or fail to charge them after every use then you will get less. My
average usage is a little heavy and I take big
currents out more regularly compared to an average user or average powerchair or
scooter. I have had 3 sets of Sonnenschein and 2 sets of MK batteries in
two powerchairs (10 batteries) so far and another set is on order.
Downside? I removed them from
my latest powerchair since it will not wheelie with them fitted. They cannot
make the large currents I demand from them. This doesn't obviously effect the
vast majority of users!
They don't like big currents. 4.0 mOhm (MK) and 6.0
(Sonnenschein - smaller battery) for both getting MUCH worse as they become
discharged. This is typical for these quality GEL type batteries. That's about
50 percent worse than say the smaller 55ah Optima deep cycle batteries or even
the cheap one at the top of this page. That means a 50 percent greater voltage
drop under heavy load. Or an inability to get full power on ramps or curbs on SOME powerchairs.
notice this as a lack of urgency on a steep hill or a lack of steering control
accuracy when going full speed (or trying to) up the same hill. It gets
worse as they become more discharged. They seem like they are discharged or a bit
"flat" when there
is actually a good bit of charge remaining that isn't really "accessible" as
such in a hurry. This isn't noticeable in an average powerchair in average use for
the vast majority of users. For most people the superior deep cycle ability of
quality GEL batteries like these is what's important and exactly what's
required by them.
A modified powerchair like mine
here used very hard on sand or
hills needs something that can
give a lot of amps fast even when partly discharged. These can both do it when
brand new (after a week) and fully charged up but long before range or distance (reduced capacity) becomes a problem
they lose that "power" needed to lift the front wheels or to climb a curb or
very steep ramp. They go "weak" rather than lose much range over time.
THINK actually happens is that voids appear in the GEL between the plates and so
they go more "high resistance" over time (No longer 4.0 mOhm / 6.0 mOhm but
Fast charging wont hurt them either
according to the MK representative I spoke to. It still needs a full overnight charge as well though as
the fast charge during the day doesn't "fully" charge the batteries and the
cells can become unbalanced without it as a result. But they still charge much
slower than AGM batteries. Even on the same sized charger due to their higher
The above information (don't like big currents) is why I personally usually choose a lower cycle life
and a dual purpose Starter/Deep Cycle battery now like the Optima, Hawker
Odyssey or even the cheap ABXAGM battery at the top of this page.. I
prefer to sacrifice cycle life on purpose for wheelie "power" on demand and steep ramp performance
even when pretty well discharged. Stuff the last few weeks and give me
I also use the same AGM Deep Cycle and Starter
batteries in my van because while they are mainly used as starter batteries they are
regularly discharged by the ramp and power doors and suspension system too. They
too get deep cycled as well! Normal factory fitted starter batteries don't
like this treatment.
In a stock powerchair with a normal user with standard gearing
and programming you don't need to worry about any of this. Just buy either of these
two batteries and chill.
Don't be tempted by cheaper batteries because you generally do get what you pay
for here. All the cheap ones have failed me one way or another!
Deep Cycle Yellow Top, and Deep Cycle Marine Blue Top batteries.
Optima batteries are slightly different in that the lead plates are coiled up
like a small Ni-Cad battery or a capacitor. They are still AGM type lead acid
batteries though. The Blue Marine batteries and the Yellow "deep Cycle"
batteries are exactly the same as each other electrically. The only difference
is that these two marine ones on my bed have some extra terminals. That's very
useful to connect the powerchairs cables to.
Either Blue (deep cycle & Starting) or Yellow 55ah Deep Cycle &
Starting batteries are therefore suitable for a powerchair.
They do not make group 24 batteries and these are Group 34 (smaller) sized. As with most
AGM type batteries they can make really big currents. Bigger than most of the rest.
More even than almost all similar sized or bigger batteries including starting only
batteries! Wheelies and ramps are no problem. They will however
probably not give an average user as many Cycles as the MK or Sonnenschein
batteries above. And they are expensive. They actually last longer in my
powerchair though than the other Gel batteries because I take
too much current from them. Too many amps.
So figures alone don't tell the
full story. These should be charged to 14.4 to 14.7 volts. Most wheelchair
chargers will be fine, and most actually overcharge the standard GEL type
batteries to a small degree which shortens their life in the interests of a
faster charge. In this way you may be surprised how long
these last! They are shorter, and smaller than most of the other batteries
on this page too.
I typically get 14 to 16 months from a set of these. That's
better than I get out of the Gel MK batteries which goes against conventional
wisdom. These should be about 20 percent worse on cycle life. Unless you
need big currents (8mph powerchair, 20 stone weight, live in a hilly area), then
the Gel MK or Sonnenschein batteries are still a better bet. Personally though I love
Elecsol batteries looked like
a cheap solution too! So I had to test them so you don't have to! Now
first of all they are NOT sealed and contain loose liquid acid. These are not
really "mobility" batteries. But they don't know that do they...
They can gas when charged and so may need
occasional topping up with distilled water. Depending on charge voltage. They cannot be transported on
aircraft either. Standard powerchair chargers are fine. They do have one large redeeming feature however. They are
100ah in the same sized package as all the rest of the 55 to 73 amp ones here on this page. The rest are 55,
56, 65, 70, 73, Amp Hours. (But there's much more to batteries than storage
capacity). Woohoo! More THEORETICAL range, cheap, and Very Deep Cycle! They use carbon fibre
They don't sulphate if discharged apparently
(CLAIMED) They can do
1000 cycles according to their website at 50 percent. So then what's the problem? Yes there
had to be one... No wheelies, no steep ramps because although they claim, to be
engine start capable and so should be able to easily zap a powerchair into life
they just aren't! To be fair I expected as much. They are about as
good as the MK batteries for current, and are "bigger" capacity so should give more range
and longer service life cheaply.
All that happens if you gun your powerchair is
that it accelerates moderately and the lights dim on the battery meter! Well on my chair at
least. Then as speed gathers its fine. Actually on my powerchair that's exactly
what MK batteries do as well. But they are not for me. On a more average soggy
they could well be OK but I cant say since I don't have one.
So they "should" be OK on a more "normal" users
moderately programmed powerchair with say a 50 to 80 amp controller. I don't
know for sure because I don't have a soggy underpowered chair to test them on.
If you need more range and you have a moderate requirement for power with smaller
powerchair, 4mph, soft programming so that you seldom actually use the full amp
capability then they should be just fine and a bargain. Just watch the battery acid levels.
Sold as a Deep Cycle and Starter battery.
Basically they are EXTREMELY good quality AGM batteries and are as good as the
and very similar electrically but larger capacity than the optima. The case is
the same size as a group 24 battery but its not as tall. Its a Group 34 battery.
These are 68 amp hour and can be deep cycled or
can easily start a truck if you wish. Lasted me 11 months (slightly less than the GEL batteries
but with better performance when discharged a good bit) but had power to
spare when needed for my modified and reprogrammed powerchair.
(Update! They were refitted out of interest and to test and are still going strong
after 13 months use which is a pleasant surprise -- must have been the cold that
They should have lasted longer as they were still "OK" but not as good as new.
And I wanted to try a new set of "silicone" batteries that had been sent by a
battery supplier free of charge. More on those another day!
If you need many
AMPS to drive your chair because you live in a hilly area with a fast tall geared "faster" powerchair or use
long steep ramps and you are fat or play wheelchair football or something -- then get
these. Great for performance due to very low internal resistance. Can be fast
charged WELL too... I charge my chair in around 1 hour. Don't expect quite as good a cycle life as you will
get from the two Gelled Acid batteries on this page though. AGM technology is better suited to
slightly lower overall total discharge levels and faster current release (and
charge). I like them. Most
people would be happier with an MK or other premium GEL battery though.
Batteries Group 24
These 75 amp hour deep cycle batteries
were sent to me to test free of charge.
I used them for about 7 months. When fully charged they gave acceptable
performance. After a little use (say half an hour walking the dog) they lost the
power to wheelie or drive up the ramp to my van with me (a fat bloke!) in a 6 mph
The 6mph is pretty relevant as the taller the gearing the more
current or amps the powerchair demands to climb a ramp. In my case with that chair that would be
100 amps as the controller was using the max power it was capable of according
to my clamp meter.
voltage just dropped away though. So the actual power needed also dropped away. For
this reason I could only recommend these for low powered or smaller powerchairs
and scooters. Range didn't seem too bad. But after 7 months was starting to
suffer and the lack of power problem was getting worse so they were replaced. I
have no idea how much they cost as they were supplied free. It could be that
they were faulty maybe? Although I doubt it. I would happily test another set if they were supplied
again. I was rather hoping that they would perform better. But again I am
not a normal user and even the very best batteries only survive 10 to 13
months with my usage style/pattern
(Electric Vehicle) Batteries
These batteries were surprisingly good. They
lasted me as long as the premium GEL batteries did and had the power to make my
modified powerchair go like it does with the AGM type batteries. Wheelies even
when 50 percent discharged too. Range and cycle
life were as good as the best.
I would recommend these unconditionally
if it were not for the fact that when they did fail after 13 months it was very sudden. So sudden
that one minute I was crossing the road with apparently good batteries in a good
state of charge and then nothing! Zilch! Totally unable to move one inch or get me going
at all or home. Battery voltage read as about 80 percent charged.
Something inside failed. Suddenly, like a
connection between cells, or something just failed like a fuse going! Never had
a battery do that before. Didn't know they could. This may have been a one off situation but the
idea of getting stuck and unable to get home -- even slowly -- really doesn't
appeal. If this doesn't worry you then get these in place of the Sonnenschein
A500 or MK GEL batteries and save some cash! f it does then spend the money. Was
going to cut one open so I could see what failed but it was too cold out
Halfords Leisure Batteries
While in the car
accessory shop Halfords, I spotted some batteries that were the
correct physical size (Group 24) and 70 Amp Hour clearly labelled "DEEP CYCLE". For about
the same price as a cheap starter battery. Mmm interesting but highly unlikely I
So I asked the guy that
was the resident battery "expert" if they would be suitable for proper deep
cycle use in the powerchair I was sat in. He said yes absolutely, and that they have a full 2 year warranty to back it up and
were perfect for a powerchair. This was going to be fun. TRUE Deep Cycle batteries
don't have 2 year warranties even if you pay four times as much since even
ones will not last 2 years if heavily cycled..
I explained that I expected them to last
about 3 months maximum. He insisted they would be perfectly fine. So
I bought a set for a laugh. They performed great, with normal range and good
"wheelie power" performance on the first
week. The second week they were getting a bit weaker and shorter in usable
After 5 or 6 weeks they couldn't get me out of the house and into my van
without the battery warning flashing... Seriously. This I expected. But Even I expected a
couple of months! So they swapped them under warranty.
5 times! That kept me
going for about 6 months in total. Then they refused to honour the
So I got all my money back. Not all batteries are equal. Be careful
how much you "save". This also put me right off ALL Halfords batteries
completely. But they keep on building NON ACCESSIBLE new buildings with no
disabled access illegally with much of the "stock" and displays upstairs
where I cant get to it so bugger them!
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