PowerMax PM4-75
#2 in StandaloneFull review
A low cost standalone converter for owners who are comfortable setting a charge voltage by hand. Its high output suits a large lithium bank.
Amazon $149$149
4.0/5
A low cost standalone converter for owners who are comfortable setting a charge voltage by hand. Its high output suits a large lithium bank.
- 100 AOutput
- YesLithium mode
- StandaloneBuild
- 2 yearsWarranty
Check price at Amazon$189
Price checked November 2, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Among the lowest prices per amp of any brand-name converter
- Adjustable fixed voltage mode lets you set the exact charge voltage your lithium battery maker asks for
- Proportional fan stays quiet at light load
- Enough output to recharge a 100 Ah battery in roughly an hour and a half or less while running loads
Cons
- Lithium charging is a manual fixed voltage setting, so a mistake with a lead acid battery can overcharge it
- Two year warranty
- Pulls up to 15 A from the AC side, so it can trip a shared 15 A circuit
The PowerMax PM4 family
Every PowerMax PM4 model we rank, smallest first. Ratings compare each against its own build.
| Model | Output | Rating | Price |
|---|---|---|---|
| PowerMax PM4-75 | 75 A | 3.9/5 | $149 |
| PowerMax PM4-100 (this one) | 100 A | 4.0/5 | $189 |
How it scores
The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its build. How we rank explains each one.
Specifications
| Model number | PM4100LK |
|---|---|
| Charging | |
| Output | 100 A |
| Lithium mode | Yes |
| Multi-stage charging | Yes |
| Build | |
| Build | Standalone |
| Fan runs only as needed | Yes |
| Remote or display | No |
| Weight | 9 lb |
| Warranty | 2 years |
Alternatives in this build
Progressive Dynamics PD9380V
#3 in StandaloneFull review
The pick for an RV owner who wants a lithium ready deck mount converter with a remote pendant in the box. Its 80 A output suits a big lithium bank.
Amazon $290$290
PowerMax PM3-55LK
#4 in StandaloneFull review
A low cost standalone converter for owners who are comfortable setting a charge voltage by hand. A common budget replacement for a WFCO 9855 class unit.
Amazon $137$137
Compare
Compare the PowerMax PM4-100 with any other RV converter charger →
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